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                                                                    EXHIBIT 10.1


                               THIRD AMENDMENT TO
                              EMPLOYMENT AGREEMENT


         WHEREAS, Ocean Energy, Inc. ("OEI") and James T. Hackett ("Executive")
have heretofore entered into an Employment Agreement (the "Agreement"),
initially effective as of September 16, 1998; and

         WHEREAS, the Agreement has been subsequently amended on two occasions
and OEI, Devon Energy Corporation ("Devon") and Executive desire to further
amend the Agreement in certain respects, contingent on, and effective upon, the
consummation of the transactions (the "Merger") contemplated by the Agreement
and Plan of Merger by and among Devon, Devon Newco Corporation, and OEI dated as
of February 23, 2003, as the same may be amended from time to time (the "Merger
Agreement");

         NOW, THEREFORE, the Agreement is amended as follows, effective as of
the "Effective Time" (which, for purposes of this Amendment, shall have the
meaning ascribed to it in the Merger Agreement):

         1. References to the "Company" in the Agreement shall mean Devon Energy
         Corporation.

         2. Paragraph 1.2 of the Agreement shall be amended to read as follows:

                           "1.2 POSITIONS. Effective as of the Effective Time,
                  the Company shall cause Executive to be appointed the
                  President and Chief Operating Officer of the Company. The
                  Company shall maintain Executive in such positions, or such
                  other positions as the parties mutually may agree, for the
                  full term of Executive's employment hereunder. The term
                  "Effective Time" shall have the meaning ascribed to it in the
                  Agreement and Plan of Merger by and among Devon Energy
                  Corporation, Devon Newco Corporation, and Ocean Energy, Inc.
                  dated as of February 23, 2003, as the same may be amended from
                  time to time (the "Merger Agreement")."

         3. Article I is amended by adding thereto a new Paragraph 1.6, Office
         Location, to read as follows:

                  "1.6 OFFICE LOCATION. The Company's principal executive
                  offices shall be maintained in the greater Oklahoma City,
                  Oklahoma area. It is anticipated that Executive will regard
                  Oklahoma City as the primary location of his office. Prior to
                  the relocation of his residence to Oklahoma City, the Company
                  shall provide Executive with appropriate airplane
                  transportation between Oklahoma City and Houston, Texas, or
                  promptly reimburse Executive for the cost thereof. In
                  addition, prior to Executive's relocation to the greater
                  Oklahoma City area (as provided below), the Company shall
                  provide Executive with, or promptly reimburse




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                  Executive for the cost of, a temporary rented, furnished
                  apartment or condominium in the greater Oklahoma City area and
                  the use of an automobile while there (the "Temporary
                  Benefits"). All utility expenses, gasoline, parking and other
                  expenses incurred by Executive and reasonably related to the
                  Temporary Benefits shall be paid by the Company. The Temporary
                  Benefits provided Executive shall be of a nature and have a
                  status appropriate for Executive's position with the Company.
                  To the extent that the Company's provision or payment of any
                  of these items is taxable compensation to Executive, the
                  Company shall pay Executive, at such applicable times, an
                  additional amount in cash such that the benefits are provided
                  to Executive without any "tax cost," whether federal, state or
                  otherwise, to him.

                           By May 1, 2004, Executive shall notify the Company
                  whether he is relocating to the greater Oklahoma City area or
                  exercising his right to terminate pursuant to paragraph
                  2.3(i). If Executive notifies the Company that he is
                  relocating, he shall use his reasonable best efforts to so
                  relocate by May 31, 2004, and if Executive has not relocated
                  to the greater Oklahoma City area by June 30, 2004, the
                  Company may terminate Executive's employment and such
                  termination shall be deemed to have been for cause pursuant to
                  paragraph 2.2(iii)."

         4. Paragraph 2.1 is amended by adding a new sentence thereto to read as
         follows:

                  "Notwithstanding the foregoing, the term of this Agreement
                  shall not expire prior to the fifth anniversary of the
                  Effective Time, unless sooner terminated pursuant to the other
                  provisions hereof."

         5. Item (D) of Paragraph 2.3(i) is amended to read as follows:

                  "(D) the Company's principal executive offices cease to be in
                  the greater Oklahoma City area or Executive is required to
                  work at an office other than the principal executive offices
                  of the Company, excluding business travel reasonably
                  consistent with Executive's past practice;"

         6. Paragraph 2.3 is further amended by adding thereto a new sentence to
         read as follows:

                  "The Company and Executive agree that Executive may not
                  terminate his employment pursuant to paragraph 2.3(i) due to a
                  change in his duties, responsibilities, positions or principal
                  place of employment based on the same as they existed
                  immediately prior to the Effective Time; provided, however,
                  the foregoing shall not prevent Executive from terminating
                  pursuant to paragraph 2.3(i)



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                  based on any change from those duties, responsibilities,
                  positions or principle place of employment as in effect
                  immediately following the Effective Time; and provided,
                  further, that upon not less than four weeks notice, Executive
                  may in all events terminate his employment on May 1, 2004 and
                  such termination shall be deemed to be for a reason
                  encompassed by paragraph 2.3(i) for which there is no
                  correction by the Company and upon such termination the
                  Company shall provide Executive with the Termination
                  Benefits."

         7. Paragraph 3.9(v) is amended by adding thereto the following:

                           "Notwithstanding the foregoing or anything in the
                  ESRP or Executive's Membership Agreement thereunder to the
                  contrary, Executive may elect, at any time prior to the
                  commencement of his benefit under the ESRP in an annuity form,
                  to receive an amount equal to 95% of the Actuarial Equivalent
                  (as such term is defined in the ESRP) of his then vested
                  Accrued Benefit under the ESRP in a single lump sum. Upon such
                  election, the non-vested portion, if any, of Executive's
                  Accrued Benefit shall be forfeited. The Company shall cause
                  the ESRP and Executive's Membership Agreement thereunder to be
                  amended as necessary to reflect this Paragraph 3.9(v)."

         8. Notwithstanding anything herein to the contrary, the Company
         continues to have the right to terminate Executive's employment at any
         time pursuant to paragraph 2.2 and any such termination by the Company,
         other than pursuant to paragraph 2.2(iii) or (iv), shall entitle
         Executive to the Termination Benefits.

         9. As amended hereby, the Agreement is specifically ratified and
         reaffirmed. If the Merger Agreement is terminated without the
         consummation of the transactions contemplated thereby, this Amendment
         shall be null and void and of no effect.




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         IN WITNESS WHEREOF, the parties hereto have executed this Amendment on
this February 23, 2003, to be effective as of the Effective Time.


                                      Ocean Energy, Inc.

                                      By:  /s/ ROBERT K. REEVES
                                           -------------------------------------
                                           Name:   Robert K. Reeves
                                           Title:  Executive Vice President,
                                                   General Counsel and Secretary



                                      Devon Energy Corporation

                                      By:  /s/ J. LARRY NICHOLS
                                           -------------------------------------
                                           Name:   J. Larry Nichols
                                           Title:  Chairman, President and
                                                   Chief Executive Officer


                                      James T. Hackett

                                      /s/ JAMES T. HACKETT
                                      ------------------------------------------
                                      James T. Hackett





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