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                                                                 EXHIBIT 10.3(c)

                                  AMENDMENT TO
                             AMERISTAR CASINOS, INC.
                              AMENDED AND RESTATED
                     MANAGEMENT STOCK OPTION INCENTIVE PLAN

                       (EFFECTIVE AS OF JANUARY 24, 2003)

This Amendment to Ameristar Casinos, Inc. Amended and Restated Management Stock
Option Incentive Plan (this "Amendment") is made and effective as of January 24,
2003.

      WHEREAS, Ameristar Casinos, Inc., a Nevada corporation (the "Company"),
maintains an Amended and Restated Management Stock Option Incentive Plan (the
"Plan"); and

      WHEREAS, the Board of Directors of the Company (the "Board") desires to
amend the Plan in certain respects as provided in this Amendment and as
permitted by Section 17 of the Plan; and

      WHEREAS, except as amended pursuant to this Amendment, the terms of the
Plan as currently in effect shall remain in full force and effect.

1. Amendment to Section 16. Section 16 of the Plan is hereby amended to read in
its entirety as follows:


"16.  ADJUSTMENTS; ACCELERATION OF VESTING IN CERTAIN CIRCUMSTANCES

            (a) If the number of outstanding shares of Common Stock is increased
      or decreased, or if such shares are exchanged for a different number or
      kind of shares or securities of the Company, through reorganization,
      merger, recapitalization, reclassification, stock dividend, stock split,
      combination of shares or other similar transaction, the aggregate number
      of shares of Common Stock subject to the Plan as provided in Section 4
      hereof, the shares of Common Stock subject to issued and outstanding
      Options under the Plan and the aggregate number of shares of Common Stock
      with respect to which Options may be granted to a single Optionee as
      provided in Section 5(c) hereof shall be appropriately and proportionately
      adjusted by the Committee. Any such adjustment in the outstanding Options
      shall be made without change in the aggregate purchase price applicable to
      the unexercised portion of the Option but with an appropriate adjustment
      in the price for each share or other unit of any security covered by the
      Option. No adjustment shall be made on account of any transaction or event
      not specifically set forth in

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      this Section 16(a), including, without limitation, the issuance of Common
      Stock for consideration.

            (b) Adjustments under Section 16(a) shall be made by the Committee,
      whose determination as to which adjustments shall be made, and the extent
      thereof, shall be final, binding and conclusive. No fractional shares of
      stock shall be issued under the Plan or in connection with any such
      adjustment.

            (c)(i) Notwithstanding any other provision of the Plan, unless
      otherwise determined by the Committee and expressly set forth in the
      agreement evidencing the Option, in the event of a Change in Control, (i)
      each Option outstanding under the Plan which is not otherwise fully vested
      or exercisable with respect to all of the shares of Common Stock at that
      time subject to such Option shall automatically accelerate so that each
      such Option shall, immediately upon the effective time of the Change in
      Control, become exercisable for all the shares of Common Stock at the time
      subject to such Option and may be exercised for any or all of those shares
      as fully vested shares of Common Stock.

            (ii) Notwithstanding any other provision of the Plan, unless
      otherwise determined by the Committee and expressly set forth in the
      agreement evidencing the Option, in the event of a Corporate Transaction,
      each Option outstanding under the Plan which is not otherwise fully vested
      or exercisable with respect to all of the shares of Common Stock at that
      time subject to such Option shall automatically accelerate so that each
      such Option shall, immediately prior to the effective time of the
      Corporate Transaction, become exercisable for all the shares of Common
      Stock at the time subject to such Option and may be exercised for any or
      all of those shares as fully vested shares of Common Stock.

            (iii) As used in the Plan, a "Change in Control" shall be deemed to
      have occurred if:

            (1)   Individuals who, as of January 24, 2003, constitute the entire
                  Board ("Incumbent Directors") cease for any reason to
                  constitute a majority of the Board; provided, however, that
                  any individual becoming a director subsequent to such date
                  whose election, or nomination for election by the Company's
                  stockholders, was approved by the vote of a majority of the
                  then Incumbent Directors (other than an election or nomination
                  of an individual whose assumption of office is the result of
                  an actual or threatened election contest relating to the
                  election of directors of the Company), also shall be an
                  Incumbent Director; or


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            (2)   Any Person (as defined below) other than a Permitted Holder
                  (as defined below) shall become the beneficial owner (as
                  defined in Rules 13d-3 and 13d-5 under the Securities Exchange
                  Act of 1934, as amended), directly or indirectly, of
                  securities of the Company representing in the aggregate fifty
                  percent (50%) or more of either (A) the then outstanding
                  shares of Common Stock or (B) the Combined Voting Power (as
                  defined below) of all then outstanding Voting Securities (as
                  defined below) of the Company; provided, however, that
                  notwithstanding the foregoing, a Change in Control shall not
                  be deemed to have occurred for purposes of this clause (2)
                  solely as the result of:

                  (Y)   An acquisition of securities by the Company which, by
                        reducing the number of shares of Common Stock or other
                        Voting Securities outstanding, increases (A) the
                        proportionate number of shares of Common Stock
                        beneficially owned by any Person to fifty percent (50%)
                        or more of the shares of Common Stock then outstanding
                        or (B) the proportionate voting power represented by the
                        Voting Securities beneficially owned by any Person to
                        fifty percent (50%) or more of the Combined Voting Power
                        of all then outstanding voting securities; or

                  (Z)   An acquisition of securities directly from the Company,
                        except that this Paragraph (Z) shall not apply to:

                        I     any conversion of a security that was not acquired
                              directly from the Company; or

                        II    any acquisition of securities if the Incumbent
                              Directors at the time of the initial approval of
                              such acquisition would not immediately after (or
                              otherwise as a result of) such acquisition
                              constitute a majority of the Board.

            (iv)  As used in the Plan, "Corporate Transaction" means (1) any
                  merger, consolidation or recapitalization of the Company (or,
                  if the capital stock of the Company is affected, any
                  subsidiary of the Company), or any sale, lease or other
                  transfer (in one transaction or a series of transactions
                  contemplated or arranged by any party as a single plan) of all
                  or substantially all of the assets of the Company (each of the
                  foregoing being an "Acquisition


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                  Transaction") where (A) the stockholders of the Company
                  immediately prior to such Acquisition Transaction would not
                  immediately after such Acquisition Transaction beneficially
                  own, directly or indirectly, shares representing in the
                  aggregate more than fifty percent (50%) of (Y) the then
                  outstanding common stock of the corporation surviving or
                  resulting from such merger, consolidation or recapitalization
                  or acquiring such assets of the Company, as the case may be
                  (the "Surviving Corporation") (or of its ultimate parent
                  corporation, if any) and (Z) the Combined Voting Power of the
                  then outstanding Voting Securities of the Surviving
                  Corporation (or of its ultimate parent corporation, if any) or
                  (B) the Incumbent Directors at the time of the initial
                  approval of such Acquisition Transaction would not immediately
                  after such Acquisition Transaction constitute a majority of
                  the board of directors of the Surviving Corporation (or of its
                  ultimate parent corporation, if any) or (2) the liquidation or
                  dissolution of the Company.

            (v) For purposes of this Section 16(c):

                  (1)   "Combined Voting Power" shall mean the aggregate votes
                        entitled to be cast generally in the election of
                        directors of a corporation by holders of the then
                        outstanding Voting Securities of such corporation;

                  (2)   "Permitted Holder" shall mean (A) the Company or any
                        trustee or other fiduciary holding securities under an
                        employee benefit plan of the Company, (B) to the extent
                        they hold securities in any capacity whatsoever, Craig
                        H. Neilsen and Ray Neilsen and their respective estates,
                        spouses, heirs, ancestors, lineal descendants,
                        stepchildren, legatees and legal representatives, and
                        the trustees of any bona fide trusts of which one or
                        more of the foregoing are the sole beneficiaries or
                        grantors thereof and (C) any Person controlled, directly
                        or indirectly, by one or more of the foregoing Persons
                        referred to in the immediately preceding clause (B),
                        whether through the ownership of voting securities, by
                        contract, in a fiduciary capacity, through possession of
                        a majority of the voting rights (as directors and/or
                        members) of a not-for-profit entity, or otherwise;

                  (3)   "Person" shall mean any individual, entity (including,
                        without limitation, any corporation (including, without
                        limitation, any charitable corporation or private
                        foundation), partnership, limited liability company,
                        trust (including, without limitation, any private,
                        charitable or split-interest trust), joint venture,
                        association or governmental body) or group (as defined
                        in Section 13(d)(3) or


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                        14(d)(2) of the Securities Exchange Act of 1934, as
                        amended, and the rules and regulations thereunder);
                        provided, however, that "Person" shall not include the
                        Company, any of its subsidiaries, any employee benefit
                        plan of the Company or any of its majority-owned
                        subsidiaries or any entity organized, appointed or
                        established by the Company or such subsidiary for or
                        pursuant to the terms of any such plan; and

                  (4)   "Voting Securities" shall mean all securities of a
                        corporation having the right under ordinary
                        circumstances to vote in an election of the board of
                        directors of such corporation."

2. Confirmation. Except as amended pursuant to this Amendment, the terms of the
Plan as currently in effect shall remain in full force and effect.


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