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                                                                   EXHIBIT 10.11


                       FIRST AMENDMENT TO CREDIT AGREEMENT


         This FIRST AMENDMENT TO CREDIT AGREEMENT is made and entered into
effective as of April 8, 2004 (this "Amendment") between MISSION RESOURCES
CORPORATION, a Delaware corporation (the "Borrower"); each of the lenders party
hereto (the "Lenders"); and WELLS FARGO BANK, NATIONAL ASSOCIATION, a national
banking association as administrative agent ("Administrative Agent") for the
Lenders.

                                    RECITALS

         A. The Borrower, the Lenders and the Administrative Agent previously
entered into that certain Credit Agreement dated as of April 8, 2004 (the
"Credit Agreement"), pursuant to which the Lenders agreed to make certain loans
to the Borrower upon the terms and conditions as provided therein.

         B. The Borrower and the Lenders desire to make certain amendments to
the Credit Agreement.

         NOW, THEREFORE, in consideration of the premises and other good and
valuable consideration and the mutual benefits, covenants and agreements herein
expressed, the parties hereto now agree as follows:

         1. All capitalized terms used in this Amendment and not otherwise
defined herein shall have the meanings ascribed to such terms in the Credit
Agreement.

         2. A new Section 10.01(p) is added as an Event of Default:

                  (p) The Borrower or any Subsidiary of the Borrower shall
            default under any Hedging Agreement or Hedging Agreements to which
            the Borrower and/or any Subsidiary and/or Subsidiaries is a party
            and to which any Lender or any Affiliate of any Lender is a party.

         3. Section 12.04 of the Credit Agreement is revised to add the term
"Super Majority Lenders," and as amended reads as follows:

            Section 12.04 Amendments. Etc. Any provision of this Agreement or
            any Security Instrument may be amended, modified or waived with the
            Borrower's and the Majority Lenders' prior written consent; provided
            that (i) no amendment, modification or waiver which extends the
            final maturity of the Loans, increases the Aggregate Maximum
            Revolving Credit Amounts, modifies the Borrowing Base, forgives the
            principal amount of any Obligations outstanding under this
            Agreement, releases any guarantor of any Obligations or releases all
            or substantially all of the collateral, reduces the interest rate
            applicable to the Loans or the fees payable to the Lenders
            generally, affects Section 2.03(a), this Section 12.04 or Section
            l2.06(a) or modifies the definition of "Majority Lenders" or "Super
            Majority Lenders," shall be effective without consent of all
            Lenders;

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            (ii) no amendment, modification or waiver which increases the
            Maximum Revolving Credit Amount or the Revolving Credit Commitment
            of any Lender shall be effective without the consent of such Lender;
            and (iii) no amendment, modification or waiver which modifies the
            rights, duties or obligations of the Agent shall be effective
            without the consent of the Agent.

         4. The parties hereto hereby acknowledge and agree that, except as
specifically supplemented and amended, changed or modified hereby, the Credit
Agreement shall remain in full force and effect in accordance with its terms.

         5. This Amendment shall be governed by, and construed in accordance
with, the laws of the State of Texas.

         6. This Amendment may be executed in two or more counterparts, and it
shall not be necessary that the signatures of all parties hereto be contained on
any one counterpart hereof; each counterpart shall be deemed an original, but
all of which together shall constitute one and the same instrument. Delivery of
an executed signature page by facsimile transmission shall be as effective as
delivery of a manually executed counterpart hereof.



                            [SIGNATURE PAGE FOLLOWS]



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         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed effective as of the date first above written.

                                          BORROWER:

                                          MISSION RESOURCES CORPORATION


                                          By:        /s/ Ann Kaesermann
                                             -----------------------------------
                                             Ann Kaesermann
                                             Vice President
                                             Accounting and Investor Relations



                                          LENDER AND AGENT:

                                          WELLS FARGO BANK, NATIONAL ASSOCIATION


                                          By:         /s/ Jeff Dalton
                                             -----------------------------------
                                             Jeff Dalton
                                             Vice President



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