UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549


                                  SCHEDULE 13G

                    Under the Securities Exchange Act of 1934
                               (AMENDMENT NO. 3)*

                           ENCORE ACQUISITION COMPANY
                           --------------------------
                                (Name of Issuer)

                     Common Stock, $0.01 Par Value Per Share
                     ---------------------------------------
                         (Title of Class of Securities)

                                    29255W100
                                    ---------
                                 (CUSIP Number)

                                   May 3, 2004
                                   -----------
                      (Date of Event which Requires Filing
                               of this Statement)



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

                                [ ] Rule 13d-1(b)
                                [ ] Rule 13d-1(c)
                                [X] 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 on 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 10 pages




-------------------                                           ------------------
CUSIP No. 29255W100                   13G                     Page 2 of 10 Pages
-------------------                                           ------------------

--------------------------------------------------------------------------------
     1 NAME OF REPORTING PERSON
       I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Warburg, Pincus Equity
       Partners, L.P.
       13-3986317
--------------------------------------------------------------------------------
     2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
                                                                         (a) [ ]

                                                                         (b) [X]

--------------------------------------------------------------------------------
     3 SEC USE ONLY

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

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

                   0
              ------------------------------------------------------------------
  NUMBER OF      6 SHARED VOTING POWER
   SHARES
BENEFICIALLY       2,919,952
  OWNED BY
              ------------------------------------------------------------------
    EACH         7 SOLE DISPOSITIVE POWER
  REPORTING
   PERSON          0
    WITH
              ------------------------------------------------------------------
                 8 SHARED DISPOSITIVE POWER

                   2,919,952
--------------------------------------------------------------------------------
     9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

       2,919,952
--------------------------------------------------------------------------------
    10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

       [ ]
--------------------------------------------------------------------------------
    11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

       9.6%
--------------------------------------------------------------------------------
    12 TYPE OF REPORTING PERSON*

       PN
--------------------------------------------------------------------------------
                       *SEE INSTRUCTION BEFORE FILLING OUT


                               Page 2 of 10 pages




-------------------                                           ------------------
CUSIP No. 29255W100                   13G                     Page 3 of 10 Pages
-------------------                                           ------------------

--------------------------------------------------------------------------------
     1 NAME OF REPORTING PERSON
       I.R.S. IDENTIFICATION NO. OF ABOVE PERSON Warburg Pincus & Co.
       13-6358475
--------------------------------------------------------------------------------
     2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
                                                                         (a) [ ]

                                                                         (b) [X]

--------------------------------------------------------------------------------
     3 SEC USE ONLY

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

       New York
--------------------------------------------------------------------------------
                 5 SOLE VOTING POWER

                   0
              ------------------------------------------------------------------
  NUMBER OF      6 SHARED VOTING POWER
   SHARES
BENEFICIALLY       2,919,952
  OWNED BY
              ------------------------------------------------------------------
    EACH         7 SOLE DISPOSITIVE POWER
  REPORTING
   PERSON          0
    WITH
              ------------------------------------------------------------------
                 8 SHARED DISPOSITIVE POWER

                   2,919,952
--------------------------------------------------------------------------------
     9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

       2,919,952
--------------------------------------------------------------------------------
    10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

       [ ]
--------------------------------------------------------------------------------
    11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

       9.6%
--------------------------------------------------------------------------------
    12 TYPE OF REPORTING PERSON*

       PN
--------------------------------------------------------------------------------
                       *SEE INSTRUCTION BEFORE FILLING OUT


                               Page 3 of 10 pages




-------------------                                           ------------------
CUSIP No. 29255W100                   13G                     Page 4 of 10 Pages
-------------------                                           ------------------

--------------------------------------------------------------------------------
     1 NAME OF REPORTING PERSON
       I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
       Warburg Pincus LLC
       13-4069737
--------------------------------------------------------------------------------
     2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
                                                                         (a) [ ]

                                                                         (b) [X]

--------------------------------------------------------------------------------
     3 SEC USE ONLY

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

       New York
--------------------------------------------------------------------------------
                 5 SOLE VOTING POWER

                   0
              ------------------------------------------------------------------
  NUMBER OF      6 SHARED VOTING POWER
   SHARES
BENEFICIALLY       2,919,952
  OWNED BY
              ------------------------------------------------------------------
    EACH         7 SOLE DISPOSITIVE POWER
  REPORTING
   PERSON          0
    WITH
              ------------------------------------------------------------------
                 8 SHARED DISPOSITIVE POWER

                   2,919,952
--------------------------------------------------------------------------------
     9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

       2,919,952
--------------------------------------------------------------------------------
    10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

       [ ]
--------------------------------------------------------------------------------
    11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

       9.6%
--------------------------------------------------------------------------------
    12 TYPE OF REPORTING PERSON*

       OO
--------------------------------------------------------------------------------
                       *SEE INSTRUCTION BEFORE FILLING OUT


                               Page 4 of 10 pages




Item 1(a)           Name of Issuer:
                    ---------------

                    Encore Acquisition Company

Item 1(b)           Address of Issuer's Principal Executive Offices:
                    ------------------------------------------------

                    777 Main Street, Suite 1400 Fort Worth, TX 76102

Items 2(a)          Name of Person Filing; Address of Principal Business Office:
                    ------------------------------------------------------------

                    Filed by and on behalf of Warburg, Pincus Equity Partners,
                    L.P., a Delaware limited partnership, ("WPEP"); Warburg
                    Pincus & Co., a New York general partnership ("WP"), which
                    is the general partner of WPEP; and Warburg Pincus LLC, a
                    New York limited liability company ("WP LLC"), which manages
                    WPEP. The members of WP LLC are substantially the same as
                    the partners of WP.

Item 2(b)           Address of Principal Business Office or, if None, Residence
                    -----------------------------------------------------------

                    The business address of each of the foregoing is 466
                    Lexington Avenue, New York, NY 10017

Item 2(c)           Citizenship:
                    ------------

                    WPEP is a Delaware limited partnership, WP is a New York
                    general partnership and WP LLC is a New York limited
                    liability company.

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

                    Common Stock, par value $0.01 per share ("Common Stock")

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

                    29255W100

Item 3              If this statement is filed pursuant to ss.ss. 240.13d-1(b)
                    ----------------------------------------------------------
                    or 240.13d-2(b) or (c), check whether the person is filing
                    ----------------------------------------------------------
                    as a:
                    -----

                    Not Applicable


                               Page 5 of 10 pages




Item 4.             Ownership:
                    ----------

                    Warburg, Pincus Equity Partners, L.P.
                    -------------------------------------

                    (a)  Amount beneficially owned: 2,919,952 shares of Common
                         Stock, as of May 3, 2004.

                    (b)  Percent of Class: 9.6%

                    (c)  (i)   Sole power to vote or direct the vote: -0-

                         (ii)  Shared power to vote or direct the vote:
                               2,919,952

                         (iii) Sole power to dispose of or direct the
                               disposition of: -0-

                         (iv)  Shared power to dispose of or direct the
                               disposition of: 2,919,952

                    Warburg Pincus & Co.
                    --------------------

                    (a)  Amount beneficially owned: 2,919,952 shares of Common
                         Stock, as of May 3, 2004.

                    (b)  Percent of Class: 9.6%

                    (c)  (i)   Sole power to vote or direct the vote: -0-

                         (ii)  Shared power to vote or direct the vote:
                               2,919,952

                         (iii) Sole power to dispose of or direct the
                               disposition of: -0-

                         (iv)  Shared power to dispose of or direct the
                               disposition of: 2,919,952

                    Warburg Pincus LLC
                    ------------------

                    (a)  Amount beneficially owned: 2,919,952 shares of Common
                         Stock, as of May 3, 2004.

                    (b)  Percent of Class: 9.6%

                    (c)  (i) Sole power to vote or direct the vote: -0-


                               Page 6 of 10 pages




                         (ii)  Shared power to vote or direct the vote:
                               2,919,952

                         (iii) Sole power to dispose of or direct the
                               disposition of: -0-

                         (iv)  Shared power to dispose of or
                               direct the disposition of: 2,919,952

Item 5              Ownership of Five Percent or Less of a Class:
                    ---------------------------------------------

                    If this statement is being filed to report the fact that as
                    of the date hereof the reporting person has ceased to be the
                    beneficial owner of more than five percent of the class of
                    securities, check the following.

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:
                    ------------------------------------------

                    Not Applicable

Item 8              Identification and Classification of Members of the Group:
                    ----------------------------------------------------------

                    Not Applicable

Item 9              Notice of Dissolution of Group:
                    -------------------------------

                    Not Applicable

Item 10             Certification:
                    --------------

                    By signing below the reporting persons certify that, to the
                    best of their knowledge and belief, the securities referred
                    to above 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 10 pages




                                    SIGNATURE
                                    ---------

     After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.

Dated: May 5, 2004

                   WARBURG, PINCUS EQUITY PARTNERS, L.P.
                   By: Warburg Pincus & Co., General Partner

                   By: /s/ Scott A. Arenare                 5/5/04
                       ------------------------------       ------
                   Name:  Scott A. Arenare                  Date
                   Title: Partner

                   WARBURG PINCUS & CO.

                   By: /s/ Scott A. Arenare                 5/5/04
                       ------------------------------       ------
                   Name:  Scott A. Arenare                  Date
                   Title: Partner

                   WARBURG PINCUS LLC

                   By: /s/ Scott A. Arenare                 5/5/04
                       ------------------------------       ------
                   Name:  Scott A. Arenare                  Date
                   Title: Member


                               Page 8 of 10 pages




                                                                       Exhibit A


Exhibit Index:

     1. Exhibit A - Joint Filing Agreement, dated as of February 7, 2002 (by and
among Warburg, Pincus Equity Partners, L.P., Warburg Pincus & Co. and Warburg
Pincus LLC pursuant to Rule 13d-1(k)(1) under the Securities Exchange Act of
1934) filed with the SEC with Form 13G on February 7, 2002, is incorporated by
reference.

The original statement shall be signed by each person on whose behalf the
statement is filed or his authorized representative. If the statement is signed
on behalf of a person by his authorized representative other than an executive
officer or general partner of the filing person, evidence of the
representative's authority to sign on behalf of such person shall be filed with
the statement, provided, however, that a power of attorney for this purpose
which is already on file with the Commission may be incorporated by reference.
The name and any title of each person who signs the statement shall be typed or
printed beneath his signature.

NOTE: Schedules filed in paper format shall include a signed original and five
copies of the schedule, including all exhibits. SEE Sec. 240.13d-7 for other
parties for whom copies are to be sent.


ATTENTION: INTENTIONAL MISSTATEMENTS OR OMISSIONS OF FACT CONSTITUTE FEDERAL
CRIMINAL VIOLATIONS (SEE 18 U.S.C. 1001)


                               Page 9 of 10 pages