------------------------------
                               UNITED STATES                                OMB APPROVAL
                    SECURITIES AND EXCHANGE COMMISSION             ------------------------------
                          Washington, D.C. 20549                   OMB Number     3235-0145
                                                                   ------------------------------
                                                                   Expires:   December 31, 2005
                                                                   ------------------------------
                                                                   Estimated average burden
                                                                   hours per response . . . 11


                              INITIAL SCHEDULE 13G


                    Under the Securities Exchange Act of 1934


                            Placer Sierra Bancshares
-------------------------------------------------------------------------------
                                (Name of Issuer)

                                  Common Stock
-------------------------------------------------------------------------------
                         (Title of Class of Securities)

                                   726079106
-------------------------------------------------------------------------------
                                 (CUSIP Number)

                                August 31, 2005
-------------------------------------------------------------------------------
             (Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

        |x|       Rule 13d-1(b)

                  Rule 13d-1(c)

                  Rule 13d-1(d)


*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).








                                PAGE 1 OF 9 PAGES





----------------------                                    ---------------------
CUSIP No.   726079106               13G                   Page  2  of  9  Pages
----------------------                                    ---------------------

-------------------------------------------------------------------------------
        
    1      NAME OF REPORTING PERSON
           I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only).

           Manulife Financial Corporation
           I.R.S. No.
-------------------------------------------------------------------------------
    2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*      (a)  |_|
                                                                  (b)  |_|
           N/A
-------------------------------------------------------------------------------
    3      SEC USE ONLY

-------------------------------------------------------------------------------
    4      CITIZENSHIP OR PLACE OF ORGANIZATION

           Canada

-------------------------------------------------------------------------------
                       5     SOLE VOTING POWER

                             -0-
                       --------------------------------------------------------
    Number of          6     SHARED VOTING POWER
      Shares
   Beneficially              -0-
     Owned by          --------------------------------------------------------
       Each            7     SOLE DISPOSITIVE POWER
    Reporting
      Person                 -0-
       With            --------------------------------------------------------
                       8     SHARED DISPOSITIVE POWER

                             -0-
-------------------------------------------------------------------------------
    9      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

           None, except through its indirect, wholly-owned subsidiaries, MFC
           Global Investment Management (U.S.A.) Limited, John Hancock Advisers,
           LLC and Independence Investments, LLC
-------------------------------------------------------------------------------
   10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

           N/A
-------------------------------------------------------------------------------
   11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

           See line 9, above
-------------------------------------------------------------------------------
   12      TYPE OF REPORTING PERSON*

           HC
-------------------------------------------------------------------------------

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!
                                PAGE 2 OF 9 PAGES






----------------------                                    ---------------------
CUSIP No.   726079106               13G                   Page  3  of  9  Pages
----------------------                                    ---------------------

-------------------------------------------------------------------------------
        
    1      NAME OF REPORTING PERSON
           I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only).

           MFC Global Investment Management (U.S.A.) Limited
-------------------------------------------------------------------------------
    2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*      (a)  |_|
                                                                  (b)  |_|
           N/A
-------------------------------------------------------------------------------
    3      SEC USE ONLY

-------------------------------------------------------------------------------
    4      CITIZENSHIP OR PLACE OF ORGANIZATION

           Canada

-------------------------------------------------------------------------------
                       5     SOLE VOTING POWER

                             -0-
                       --------------------------------------------------------
    Number of          6     SHARED VOTING POWER
      Shares
   Beneficially              498
     Owned by          --------------------------------------------------------
       Each            7     SOLE DISPOSITIVE POWER
    Reporting
      Person                 -0-
       With            --------------------------------------------------------
                       8     SHARED DISPOSITIVE POWER

                             498
-------------------------------------------------------------------------------
    9      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

           498
-------------------------------------------------------------------------------
   10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

           N/A
-------------------------------------------------------------------------------
   11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

           .003%
-------------------------------------------------------------------------------
   12      TYPE OF REPORTING PERSON*

           IA
-------------------------------------------------------------------------------

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!
                                PAGE 3 OF 9 PAGES






----------------------                                    ---------------------
CUSIP No.   726079106               13G                   Page  4  of  9  Pages
----------------------                                    ---------------------

-------------------------------------------------------------------------------
        
    1      NAME OF REPORTING PERSON
           I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only).

           Independence Investments, LLC

-------------------------------------------------------------------------------
    2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*      (a)  |_|
                                                                  (b)  |_|
           N/A
-------------------------------------------------------------------------------
    3      SEC USE ONLY

-------------------------------------------------------------------------------
    4      CITIZENSHIP OR PLACE OF ORGANIZATION

           Delaware
-------------------------------------------------------------------------------
                       5     SOLE VOTING POWER

                             1,196,500
                       --------------------------------------------------------
    Number of          6     SHARED VOTING POWER
      Shares
   Beneficially              -0-
     Owned by          --------------------------------------------------------
       Each            7     SOLE DISPOSITIVE POWER
    Reporting
      Person                 1,196,500
       With            --------------------------------------------------------
                       8     SHARED DISPOSITIVE POWER

                             -0-
-------------------------------------------------------------------------------
    9      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

           1,196,500
-------------------------------------------------------------------------------
   10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

           N/A
-------------------------------------------------------------------------------
   11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

           7.9%
-------------------------------------------------------------------------------
   12      TYPE OF REPORTING PERSON*

           IA
-------------------------------------------------------------------------------

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!
                                PAGE 4 OF 9 PAGES






----------------------                                    ---------------------
CUSIP No.   726079106               13G                   Page  5  of  9  Pages
----------------------                                    ---------------------

-------------------------------------------------------------------------------
        
    1      NAME OF REPORTING PERSON
           I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (entities only).

           John Hancock Advisers, LLC
-------------------------------------------------------------------------------
    2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*      (a)  |_|
                                                                  (b)  |_|
           N/A
-------------------------------------------------------------------------------
    3      SEC USE ONLY

-------------------------------------------------------------------------------
    4      CITIZENSHIP OR PLACE OF ORGANIZATION

           Delaware
-------------------------------------------------------------------------------
                       5     SOLE VOTING POWER

                             319,500
                       --------------------------------------------------------
    Number of          6     SHARED VOTING POWER
      Shares
   Beneficially              -0-
     Owned by          --------------------------------------------------------
       Each            7     SOLE DISPOSITIVE POWER
    Reporting
      Person                 319,500
       With            --------------------------------------------------------
                       8     SHARED DISPOSITIVE POWER

                             -0-
-------------------------------------------------------------------------------
    9      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

           319,500
-------------------------------------------------------------------------------
   10      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*

           N/A
-------------------------------------------------------------------------------
   11      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

           2.1%
-------------------------------------------------------------------------------
   12      TYPE OF REPORTING PERSON*

           IA
-------------------------------------------------------------------------------

                      *SEE INSTRUCTIONS BEFORE FILLING OUT!
                                PAGE 5 OF 9 PAGES



Attention:  Intentional  misstatements  or omissions of fact constitute  Federal
            criminal violations (See 18 U.S.C. 1001)

         Item 1(a)    Name of Issuer:
                      ---------------
                      Placer Sierra Bancshares

         Item 1(b)    Address of Issuer's Principal Executive Offices:
                      ------------------------------------------------
                      525 J Street
                      Sacramento, California 95814

         Item 2(a)    Name of Person Filing:
                      ----------------------
                      This filing is made on behalf of Manulife Financial
                      Corporation ("MFC"), and MFC's indirect, wholly-owned
                      subsidiaries Independence Investments, LLC ("IIA") and
                      John Hancock Advisers LLC ("JHA"), and MFC Global
                      Investment Management (U.S.A.) Limited ("MFC Global").

         Item 2(b)    Address of the Principal Offices:
                      ---------------------------------
                      The principal business offices of MFC and MFC Global are
                      located at 200 Bloor Street, East, Toronto, Ontario, 
                      Canada, M4W 1E5; IIA is located at 53 State Street, 
                      Boston, MA 02109 and JHA is located at 601 Congress
                      Street, Boston, Massachusetts 02210.

         Item 2(c)    Citizenship:
                      ------------
                      MFC and MFC Global are organized and exist under the laws
                      of Canada. IIA and JHA are organized and exist under the
                      laws of the State of Delaware.

         Item 2(d)    Title of Class of Securities:
                      -----------------------------
                      Common Stock

         Item 2(e)    CUSIP Number:
                      -------------
                      726079106

         Item 3       If the Statement is being filed pursuant to Rule 13d-1(b),
                      or 13d-2(b), check whether the person filing is a:

                      MFC:        (e) (X) Parent Holding Company, in accordance
                                          with ss.240.13d-1(b)(ii)(G).

                      JHA:        (e) (X) Investment Adviser registered under
                                          ss.203 of the Investment Advisers Act
                                          of 1940.

                      IIA:        (e) (X) Investment Adviser registered under
                                          ss.203 of the Investment Advisers Act
                                          of 1940.

                      MFC Global: (e) (X) Investment Adviser registered under
                                          ss.203 of the Investment Advisers Act
                                          of 1940.
         Item 4       Ownership:
                      ----------

                      (a)  Amount Beneficially Owned:
                           MFC Global has indirect beneficial ownership of 498
                           shares of Common Stock, JHA has indirect beneficial
                           ownership of 319,500 shares of Common Stock and IIA
                           has indirect beneficial ownership of 1,196,500 shares
                           of Common Stock. Through its parent-subsidiary 
                           relationship to IIA, JHA, and MFC Global, MFC may be
                           deemed to have indirect, beneficial ownership of all
                           of the shares held by these entities.


                                PAGE 6 OF 9 PAGES



                      (b)  Percent of Class:
                           Of the 14,956,529 shares outstanding as of August
                           8, 2005 according to the issuer's quarterly report
                           on form 10-Q for the period ended June 30, 2005,
                           MFC Global held .003%, IIA held 7.9% and JHA held 
                           2.1%.

                      (c)  Number of shares as to which the person has:

                             (i)    sole power to vote or to direct the vote:
                                    IIA and JHA each has sole power to dispose
                                    or to direct the disposition of the shares
                                    of Common Stock directly beneficially owned
                                    by each of them. JHA has sole power to
                                    dispose or to direct the disposition of the 
                                    shares of Common Stock deemed beneficially 
                                    owned by it pursuant to an advisory 
                                    agreement.

                             (ii)   shared power to vote or to direct the vote:
                                    MFC Global has shared power to vote or to
                                    direct the voting of the shares it 
                                    beneficially owns.

                             (iii)  sole power to dispose or to direct the
                                    disposition of:
                                    IIA and JHA each has sole power
                                    to dispose or to direct the disposition of
                                    the shares of Common Stock directly 
                                    beneficially owned by each of them. JHA has
                                    sole power to dispose or to direct the 
                                    disposition of the shares of Common Stock 
                                    deemed beneficially owned by it pursuant to
                                    an advisory agreement.

                             (iv)   shared power to dispose or to direct the
                                    disposition of:
                                    MFC Global has shared power to dispose or to
                                    direct the disposition of the shares it 
                                    beneficially owns.


         Item 5       Ownership of Five Percent or Less of a Class:
                      --------------------------------------------
                      Not applicable.

         Item 6       Ownership of More than Five Percent on Behalf of Another
                      Person:
                      --------------------------------------------------------
                      Not applicable.

         Item 7       Identification and Classification of the Subsidiary which
                      Acquired the Security Being Reported on by the Parent 
                      Holding Company:
                      ---------------------------------------------------------
                      See Items 3 and 4 above.

         Item 8       Identification and Classification of Members of the Group:
                      ----------------------------------------------------------
                      Not applicable.

         Item 9       Notice of Dissolution of a Group:
                      ---------------------------------
                      Not applicable.

         Item 10      Certification:
                      --------------
                      By signing below the undersigned certifies that, to the
                      best of its knowledge and belief, the securities referred
                      to above were acquired and are held in the ordinary course
                      of business and were not acquired and are not held for the
                      purpose of or with the effect of changing or influencing
                      the control of the issuer of the securities and were not
                      acquired and are not held in connection with or as a
                      participant in any transaction having that purpose or
                      effect.



                                PAGE 7 OF 9 PAGES




                                    SIGNATURE

     After reasonable inquiry and to the best of its knowledge and belief,  each
of the undersigned certifies that the information set forth in this statement is
true, complete and correct.

                               Manulife Financial Corporation

                               By:      /s/ Christer V. Ahlvik
                                        ----------------------
                                        Name:   Christer V. Ahlvik
                                        Title:  Vice President and
Dated:  September 12, 2005                      Corporate Secretary

                               John Hancock Advisers, LLC

                               By:      Al Ouellette
                                        ------------
                                        Name:   Al Ouellette
                                        Title:  Assistant Vice President and
Dated:  September 12, 2005                      Senior Counsel

                               Independence Investments, LLC

                               By:      /s/ Patti Thompson
                                        ------------------
                                        Name:   Patti Thompson
Dated:  September 12, 2005              Title:  Chief Compliance Officer

                               MFC global Investment Management (U.S.A.) Limited

                               By:      /s/ Gordon Pansegrau
                                        --------------------
                                        Name:   Gordon Pansegrau
Dated:  September 12, 2005              Title:  General Counsel, Secretary and
                                                Chief Compliance officer



                                PAGE 8 OF 9 PAGES




EXHIBIT A
                             JOINT FILING AGREEMENT

     Manulife Financial Corporation, Independence Investments, LLC, John Hancock
Advisers,  LLC and MFC Global Investment  Management (U.S.A.) Limited agree that
the Initial  Schedule 13G to which this  Agreement is attached,  relating to the
Common Stock of Placer Sierra Bancshares is filed on behalf of each of them.


                               Manulife Financial Corporation

                               By:      /s/ Christer V. Ahlvik
                                        ----------------------
                                        Name:   Christer V. Ahlvik
                                        Title:  Vice President and
Dated:  September 12, 2005                      Corporate Secretary

                               John Hancock Advisers, LLC

                               By:      Al Ouellette
                                        ------------
                                        Name:   Al Ouellette
                                        Title:  Assistant Vice President and
Dated:  September 12, 2005                      Senior Counsel

                               Independence Investments, LLC

                               By:      /s/ Patti Thompson
                                        ------------------
                                        Name:   Patti Thompson
Dated:  September 12, 2005              Title:  Chief Compliance Officer

                               MFC Global Investment Management (U.S.A.) Limited

                               By:      /s/ Gordon Pansegrau
                                        --------------------
                                        Name:   Gordon Pansegrau
Dated:  September 12, 2005              Title:  General Counsel, Secretary and
                                                Chief Compliance officer



                                PAGE 9 OF 9 PAGES