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Exhibit 10(a)

Draft of November 13, 2001

AMENDMENT TO STOCK PURCHASE AGREEMENT AND COLLATERAL AGREEMENT

    AMENDMENT, dated as of September 15, 2001 (this "Amendment"), to the Stock
Purchase Agreement, dated as of September 8, 2000, as amended by the First
Amendment thereto, dated as of January 2, 2001, and by the Second Amendment
thereto, dated as of March 21, 2001 (as so amended, the "Stock Purchase
Agreement"), among Bank of America, N.A., a national banking association, as
Share Seller ("Share Seller"), MBG Trust, a Delaware business trust (the
"Trust"), and Mandalay Resort Group, a Nevada corporation ("Share Purchaser"),
and to the Collateral Agreement, dated as of September 8, 2000 (the "Collateral
Agreement"), among Share Purchaser, Share Seller, the Trust and Banc of America
Securities LLC, a Delaware limited liability company ("Collateral Agent").

W I T N E S S E T H

    WHEREAS, the parties have entered into the Stock Purchase Agreement and the
Collateral Agreement; and

    WHEREAS, the parties desire to provide for the modification of the Stock
Purchase Agreement and the Collateral Agreement as set forth herein.

    NOW THEREFORE, in consideration of their mutual covenants herein contained,
the parties hereto, intending to be legally bound, hereby mutually covenant and
agree as follows:

    1.  Defined Terms. Capitalized terms used but not defined herein have the
meanings specified in the Stock Purchase Agreement or the Collateral Agreement,
as the case may be. Terms defined herein shall be deemed to be defined in the
Stock Purchase Agreement.

    2.  Amendments to Definitions.

(a)Section 1.1 of the Stock Purchase Agreement is hereby amended as follows:

(i)in the definition of "Maximum Deliverable Shares", the number "12,500,000"
shall be replaced with "15,000,000";

(ii)in the definition of "Maximum Initial Amount", the number "$125 million"
shall be replaced with "$145 million"; and

(iii)in the definition of "Maximum Initial Shares", the number "8.0%" shall be
replaced with "8.5%" and the phrase "in the Initial Period" shall be deleted.

(b)The definition of "Spread" in Section 1.1 of the Stock Purchase Agreement
shall be amended and restated in its entirety to read as follows:

    "Spread" means (i) with respect to any Daily Additional Share Amount or the
portion of the Aggregate Forward Amount accumulated during the Additional
Purchase Period, 195 basis points per annum and (ii) otherwise, 150 basis points
per annum (collectively, the "Initial Spread"), as such rates may be adjusted
from time to time pursuant to Section 7.9; provided that if an Event of Default
with respect to Share Purchaser has occurred and is continuing, the
otherwise-prevailing spread (as so adjusted) shall be increased by 100 basis
points per annum. In the event of an Optional Prepayment or a Mandatory
Prepayment in part, or other reduction in part of the Aggregate Forward Amount,
the Calculation Agent shall allocate in its discretion the Prepayment Amount or
amount of such other reduction, as the case may be, between the portions of the
Aggregate Forward Amount described in clauses (i) and (ii) of the preceding
sentence.

(c)For the avoidance of doubt, the amendments made by subsection (a) above shall
not be deemed to affect the obligations of the parties in respect of the Initial
Period.

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    3.  Interest Accrual Period Adjustment. Notwithstanding anything to the
contrary in the Stock Purchase Agreement, (i) the Interest Accrual Period
commencing on and including July 1, 2001, will end on and include October 31,
2001; and (ii) the next following Interest Accrual Period will commence on and
include November 1, 2001, and will end on and include December 31, 2001.

    4.  Interim Settlement Adjustment. Notwithstanding anything to the contrary
in the Stock Purchase Agreement, the parties will not be required to perform
their respective obligations under Section 2.5 of the Stock Purchase Agreement
in respect of the last Exchange Business Day of any calendar quarter during the
term of the Stock Purchase Agreement, but shall instead perform such obligations
in respect of the last Exchange Business Day of the month next following such
calendar quarter as though it were the last Exchange Business Day of a calendar
quarter.

    5.  Additional Purchase of Shares. (a) During the period commencing on and
including October 4, 2001 and ending on and including the Final Additional
Purchase Date (as defined below) (the "Additional Purchase Period"), Share
Seller shall, subject to the next sentence, use reasonable efforts to purchase
or cause the purchase of Shares (the "Additional Shares") with an Aggregate
Additional Share Amount (as defined below) as close as practicable to (taking
into account any Purchase Suspensions), but in no event greater than,
$20,000,000, in such manner, at such prices and at such times as Share Seller,
in its sole discretion, shall determine. The provisions of the second and third
sentences of Section 2.2(a) and Sections 2.2(b) and (c) of the Stock Purchase
Agreement shall apply to such purchases, with references therein to an Initial
Period Date being deemed to refer to any Exchange Business Day in the Additional
Purchase Period (each, an "Additional Purchase Date"). With respect to the
purchase of Additional Shares on any Additional Purchase Date, each party hereby
makes the representations and warranties, and agrees to comply with the
covenants and agreements, set forth in the Stock Purchase Agreement that would
be applicable to such party in connection with the purchase of Shares on any
Initial Period Date.

(b)On the earliest to occur of (i) the first Additional Purchase Date on which
the number of Initial Shares plus the number of Additional Shares purchased on
or prior to such date equals the Maximum Initial Shares, (ii) the first
Additional Purchase Date on which the Aggregate Forward Amount plus the
Aggregate Additional Share Amount equals the Maximum Initial Amount,
(iii) written direction of Share Purchaser delivered to the Trust and Share
Seller that the Additional Purchase Period shall terminate, (iv) October 31,
2001 and (v) any Optional Prepayment Date, Mandatory Prepayment Event or any
Event of Default with respect to Share Purchaser (the earliest of the dates
described in clauses (i) through (v), the "Final Additional Purchase Date"), the
Additional Purchase Period shall terminate and Share Seller shall cease
purchasing or causing the purchase of Additional Shares and shall promptly
prepare and deliver a schedule to Share Purchaser, which shall state the number
of Additional Shares purchased and the Aggregate Additional Share Amount as of
the end of the Additional Purchase Period.

(c)Upon the occurrence of the Final Additional Purchase Date, (i) the Aggregate
Forward Amount shall be increased by the Aggregate Additional Share Amount and
(ii) the Number of Shares shall be increased by the number of Additional Shares.
Notwithstanding anything to the contrary herein, (x) such increases shall not
apply for purposes of the calculation of Interest Costs for the Interest Payment
Date on the last Exchange Business Day of October 2001 and (y) such increases
shall apply for purposes of the determination of the obligations of Share
Purchaser and Share Seller under Section 2.5 of the Stock Purchase Agreement in
respect of such date.

    6.  Interest Payments and Commissions. On the last Business Day of the
calendar month in which the Final Additional Purchase Date occurs, Share
Purchaser shall pay to or as directed by Share Seller an amount in cash equal to
the sum of (i) the aggregate Additional Interest Costs for each Daily

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Additional Share Amount and (ii) the product of the Purchase Commission and the
number of Additional Shares purchased pursuant to Section 5(a) above during the
Additional Purchase Period (the "Additional Commission Cost"). Share Purchaser
shall be entitled, in lieu of its obligations under this Section 6, to pay such
amounts in accordance with Section 2.3(c) of the Stock Purchase Agreement as
though such amounts were an Interest Cost and the date of payment therefor were
an Interest Payment Date.

    7.  Repricing. Section 7.9 of the Stock Purchase Agreement is hereby amended
(i) by (i) replacing "to reflect" with "such that (x) the applicable Spread
under clause (ii) of the definition thereof reflects" and (ii) by inserting at
the end of the first sentence the phrase "and (y) the applicable Spread under
clause (i) of the definition thereof is 45 basis points per annum above the
spread determined pursuant to clause (x)".

    8.  Structuring Fee. On October 4, 2001, Share Purchaser shall pay to Share
Seller an amount equal to $50,000.

    9.  Additional Definitions. As used herein, the following terms shall have
the indicated meanings:

    "Additional Interest Cost" means, for each Daily Additional Share Amount, an
amount equal to the product of (w) such Daily Additional Share Amount, (x) the
applicable Initial LIBOR Rate plus the Spread, (y) the actual number of days
elapsed in the period from and including the related Additional Purchase
Settlement Date to and including the last calendar day of the calendar month in
which the Final Additional Purchase Date occurs, and (z) 1/360. For purposes of
this provision, references to "Initial Period Settlement Date" and "Daily
Aggregate Forward Amount" in the definition of Initial LIBOR Rate (and in the
definitions of terms used therein) shall be deemed to be "Additional Purchase
Settlement Date" and "Daily Additional Share Amount," respectively.

    "Additional Purchase Settlement Date" means, for any Additional Purchase
Date on which Additional Shares are purchased, the third Exchange Business Day
following such date.

    "Aggregate Additional Share Amount" means, on any date of determination, the
sum of the Daily Additional Share Amounts for each Additional Purchase Date
occurring on or prior to such date of determination.

    "Daily Additional Share Amount" means, for any Additional Purchase Date, the
aggregate purchase price of the Additional Shares (excluding the Purchase
Commission) purchased on such date, if any, by or on behalf of Share Seller.

    10.  Collateral Agreement. (a) The parties agree that the Additional Shares
shall constitute Collateral Shares and Initial Shares for purposes of the
Collateral Agreement and all the documents relating thereto.

(b)For purposes of Section 2.1 of the Collateral Agreement, references to an
Initial Period Date shall be deemed to include any Additional Purchase Date.

    11.  Adjustments. The Calculation Agent shall make appropriate adjustments,
if any, to interest and other calculations under the Stock Purchase Agreement as
a result of this Amendment, including, without limitation, to account for the
amendment to the definition of Spread. Provisions of the Stock Purchase
Agreement authorizing appropriate adjustments to reflect purchases of Shares
during the Initial Period shall be deemed to authorize appropriate adjustments
to reflect the purchase of Additional Shares during the Additional Purchase
Period.

    12.  Effect of the Amendment. Except as amended hereby, the Stock Purchase
Agreement and the Collateral Agreement are ratified and confirmed and continue
in full force and effect. All references to the Stock Purchase Agreement or the
Collateral Agreement in the Stock Purchase Agreement, the

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Collateral Agreement or any document related thereto shall for all purposes
constitute references to the Stock Purchase Agreement or the Collateral
Agreement, as the case may be, as amended hereby. For the avoidance of doubt,
the provisions of Section 9.10 of the Stock Purchase Agreement apply to this
Amendment as if such provisions were stated in full herein.

    13.  Miscellaneous. This Amendment constitutes the entire agreement and
understanding of the parties with respect to its subject matter and supersedes
all oral communication and prior writings with respect thereto. No amendment,
modification or waiver in respect of this Amendment will be effective unless in
writing (including a writing evidenced by a facsimile transmission) and executed
by each of the parties. This Amendment may be executed and delivered in
counterparts (including by facsimile transmission), each of which will be deemed
an original. The headings used in this Amendment are for convenience of
reference only and are not to affect the construction of or to be taken into
consideration in interpreting this Amendment.

    14.  Governing Law. THIS AMENDMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK (WITHOUT GIVING EFFECT TO
CHOICE OF LAW PRINCIPLES).

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    IN WITNESS WHEREOF, this Amendment has been duly executed as of the date
first above written.

MANDALAY RESORT GROUP, as Share Purchaser
By:
 
/s/ GLENN SCHAEFFER   

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Name: Glenn Schaeffer
Title: President, Chief Financial Officer
and Treasurer
MBG TRUST, as the Trust
By:
 
WILMINGTON TRUST COMPANY,
not in its individual capacity but solely
as Trustee
 
 
By:
 
/s/ JEANNE M. OLLER   

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Name: Jeanne M. Oller
Title: Financial Services Officer
BANK OF AMERICA, N.A., as Share Seller
By:
 
/s/ WILLIAM C. CACCAMISE   

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Name: William C. Caccamise
Title: Authorized Signatory
BANC OF AMERICA SECURITIES LLC, as
Collateral Agent
By:
 
/s/ WILLIAM C. CACCAMISE   

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Name: William C. Caccamise
Title: Managing Director

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