FOURTH AMENDMENT TO CREDIT AGREEMENT AND LIMITED WAIVER

Exhibit 10.1

FOURTH AMENDMENT TO CREDIT AGREEMENT

AND LIMITED WAIVER

THIS FOURTH AMENDMENT TO CREDIT AGREEMENT (this “ Amendment ”) is entered into as of August 31, 2009, between GULFPORT ENERGY CORPORATION , a Delaware corporation (the “ Borrower ”), each lender from time to time party hereto (collectively, the “ Lenders ” and individually a “ Lender ”), and BANK OF AMERICA, N.A. , a national banking association, as a Lender and as Administrative Agent (in such latter capacity, “ Agent ”). Capitalized terms used but not defined in this Amendment have the meaning given them in the Credit Agreement (defined below).

RECITALS

A. Borrower, Lenders and Agent entered into that certain Credit Agreement dated as of March 11, 2005 (as amended by the First Amendment to Credit Agreement dated March 20, 2007, the Second Amendment to Credit Agreement dated July 19, 2007, the Third Amendment to Credit Agreement dated December 20, 2007, and as may be further amended, restated or supplemented from time to time, the “ Credit Agreement ”).

B. Borrower, Lenders and Agent have agreed to amend the Credit Agreement, subject to the terms and conditions of this Amendment, in order to, among other things, recharacterize a certain portion of the Obligations as a new term loan.

NOW THEREFORE, for good and valuable consideration, the receipt and sufficiency of which are acknowledged, the undersigned hereby agree as follows:

1. Amendments to Credit Agreement .

(a) Section 1.01 of the Credit Agreement is hereby amended by adding the following definitions in their proper alphabetical order:

“ Equity Issuance ” means any issuance of equity interests (including any preferred equity securities) by the Borrower or any of its Subsidiaries other than equity interests issued (i) to the Borrower or any of its Subsidiaries; (ii) pursuant to employee or director and officer benefit or dividend reinvestment plans or stock option or purchaser plans ; (iii) as consideration in connection with or to fund any investment by the Borrower or any of its Subsidiaries in any other Person pursuant to which such Person shall become a Subsidiary or shall be merged into or consolidated with the Borrower or any of its Subsidiaries; or (iv) pursuant to any outstanding warrants to purchase common stock pursuant to any of the approximately 66,000 outstanding warrants to purchase common stock issued by the Company in 2002 in the ordinary course of business .

“ Equity Issuance Proceeds ” means, with respect to any Equity Issuance, all cash and cash equivalents received by the Borrower or any of

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its Subsidiaries from such Equity Issuance after payment of, or provision for, all reasonable brokerage commissions, investment banking fees, attorneys’ fees, accountants’ fees, underwriting discounts and commissions, taxes and other reasonable out-of-pocket fees, costs and expenses actually incurred.

“ Forward Sales Contracts ” means those certain forward sales contracts entered into among the Borrower and third parties in the ordinary course of business related to sales of Hydrocarbons.

“ Fourth Amendment Effective Date ” means August 31, 2009.

“ Net Cash Proceeds ” means (a) in connection with any Disposition or Recovery Event, the proceeds thereof in the form of cash and cash equivalents (including any such proceeds received by way of deferred payment of principal pursuant to a note or installment receivable or purchase price adjustment receivable or otherwise, but only as and when received) of such Disposition or Recovery Event, net of attorneys’ fees, accountants’ fees, investment banking fees and insurance consultant fees, amounts required to be applied to the repayment of Indebtedness secured by a Lien permitted hereunder on any asset which is the subject of such Disposition or Recovery Event (other than any Lien pursuant to a Loan Document) and other customary fees, costs and expenses actually incurred in connection therewith, taxes paid or reasonably estimated to be payable as a result thereof within two years of the date of the relevant Disposition or Recovery Event as a result of any gain recognized in connection therewith (after taking into account any applicable tax credits or deductions and any tax sharing arrangements) and, to the extent in the ordinary course of business and customary in the Borrower’s line of business, all distributions and other payments required to be made pursuant to partnership agreements, limited liability company organizational documents, joint venture agreements, operating agreements, production sharing agreements, pooling arrangements and other agreements relating to the assets so Disposed of, and amounts reserved for purchase price adjustments and post-closing liabilities, (b) in connection with any issuance or sale of debt securities or instruments or the incurrence of loans, the cash proceeds or cash equivalents received from such issuance or incurrence, net of attorneys’ fees, investment banking fees, brokerage, finder’s or similar fees, accountants’ fees, underwriting discounts and commissions and other customary fees and expenses actually incurred in connection therewith, and (c) in connection with the settlement, unwinding or termination of a Swap Contract, the cash proceeds or cash equivalents received, net of attorneys’ fees, costs, charges and other customary fees and expenses actually incurred in connection therewith.

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“ Recovery Event ” means any settlement of or payment in respect of any property or casualty insurance claim (excluding any claim in respect of business interruption) or any condemnation proceeding relating to any asset of the Borrower or any of its Subsidiaries.

“ Term Loan ” has the meaning specified in Section 2.01(b) .

“ Term Loan Notice ” means a written notice of a continuation of the Term Loan pursuant to Section 2.02(a) , which shall include (a) the duration of the Interest Period for such continuation or (b) a conversion of the Term Loan from (i) a Eurodollar Rate Loan to a Base Rate Loan or (ii) a Base Rate Loan to a Eurodollar Rate Loan.

“ Term Loan Principal Amount ” means $14,020,525.

“ Term Pro Rata Share ” means, with respect to each Lender, at any time, a fraction (expressed as a percentage, carried out to the ninth decimal place), the numerator of which is the amount of the portion of the Term Loan held by such Lender at such time and the denominator of which is the outstanding principal amount of the Term Loan. The initial Term Pro Rata Share is set out opposite the name of such Lender on Schedule 2.01(b) or in the Assignment and Assumption Agreement pursuant to which such Lender becomes a party hereto, as applicable.

(b) Section 1.01 of the Credit Agreement is hereby amended by replacing the following definitions in proper alphabetical order:

“ Applicable Rate ” means: (a) With respect to any Revolving Loan and with respect to Letters of Credit, the following percentages per annum, based upon the Utilization Percentage:

Any increase or decrease in the Applicable Rate resulting from a change in the Utilization Percentage shall become effective on the date such change occurs.

(b) With respect to the Term Loan, a percentage per annum equal to four percent (4.00%). To the extent the Term Loan is converted to a Base Rate Loan as permitted hereunder, the Applicable Rate shall be a percentage per annum equal to 3.00%.

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“ Availability Period ” means the period from and including the Closing Date to the earlier of (a) the Maturity Date, and (b) the date of termination of the commitment of each Lender to make Revolving Loans and of the obligation of Agent to make L/C Credit Extensions pursuant to Section 8.02 .

“ Base Rate ” means for any day a fluctuating rate per annum equal to the highest of (a) the Federal Funds Rate plus  ¹ / 2 of 1%, (b) the rate of interest in effect for such day as publicly announced from time to time by Bank of America as its “prime rate” and (c) the sum of (i) 1.00% plus (ii) the Eurodollar Rate (for an Interest Period of one month, determined in accordance with the definition of Eurodollar Rate). The “prime rate” is a rate set by Bank of America based upon various factors including Bank of America’s costs and desired return, general economic conditions and other factors, and is used as a reference point for pricing some loans, which may be priced at, above, or below such announced rate. Any change in such rate announced by Bank of America shall take effect at the opening of business on the day specified in the public announcement of such change.

“ Borrowing ” means a borrowing consisting of simultaneous Revolving Loans of the same Type and, in the case of Revolving Loans that are Eurodollar Rate Loans, having the same Interest Period made by each of Lenders pursuant to Section 2.01(a) .

“ Interest Payment Date ” means, (a) as to any Eurodollar Rate Loan, the last day of each Interest Period applicable to such Loan and the Maturity Date ; provided that, that if any Interest Period for a Eurodollar Rate Loan exceeds one month, the respective dates that fall on the last Business Day of each month after the beginning of such Interest Period shall also be Interest Payment Dates; and (b) as to any Base Rate Loan, the last Business Day of each month.

“ Interest Period ” means as to each Eurodollar Rate Loan, the period commencing on the date such Eurodollar Rate Loan is disbursed or converted to or continued as a Eurodollar Rate Loan and ending on the date one, two or three months thereafter (subject to availability), as selected by Borrower in its Revolving Loan Notice or Term Loan Notice, as applicable; provided that :

(a) any Interest Period that would otherwise end on a day that is not a Business Day shall be extended to the next succeeding Business Day unless, such Business Day falls in another calendar month, in which case such Interest Period shall end on the next preceding Business Day;

(b) any Interest Period that begins on the last Business Day of a calendar month (or on a day for which there is no

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numerically corresponding day in the calendar month at the end of such Interest Period) shall end on the last Business Day of the calendar month at the end of such Interest Period; and

(c) no Interest Period shall extend beyond the Maturity Date.

“ Loans ” means an extension of credit by a Lender to Borrower under Article II in the form of a Revolving Loan or the Term Loan.

“ Outstanding Amount ” means (a) with respect to Revolving Loans on any date, the aggregate outstanding principal amount thereof after giving effect to any borrowings and prepayments or repayments of Revolving Loans, as the case may be, occurring on such date; (b) with respect to the Term Loan on any date, the aggregate outstanding principal amount thereof after giving effect to any prepayments or repayments of the Term Loan, as the case may be, occurring on such date; and (c) with respect to any L/C Obligations on any date, the amount of such L/C Obligations on such date after giving effect to any L/C Credit Extension occurring on such date and any other changes in the aggregate amount of the L/C Obligations as of such date, including as a result of any reimbursements of outstanding unpaid drawings under any Letters of Credit or any reductions in the maximum amount available for drawing under Letters of Credit taking effect on such date.

“ Request for Credit Extension ” means (a) with respect to a Borrowing, conversion or continuation of Revolving Loans, a Revolving Loan Notice, (b) with respect to any continuation of the Term Loan, a Term Loan Notice and (c) with respect to an L/C Credit Extension, a Letter of Credit Application.

“ Revolving Loan ” has the meaning specified in Section 2.01(a) .

“ Revolving Loan Notice ” means a notice of (a) a Borrowing, (b) a conversion of Revolving Loans from one Type to the other, or (c) a continuation of Revolving Loans that are Eurodollar Rate Loans, pursuant to Section 2.02(a) , which, if in writing shall be substantially in the form of Exhibit A .

“ Total Outstandings ” means the aggregate Outstanding Amount of all Revolving Loans and all L/C Obligations.

(c) Section 2.01 of the Credit Agreement is hereby amended to add “(a)” before the heading “ Revolving Loans ” and to replace every reference to “ 2.01 ” with “ 2.01(a) ” and every reference to “ 2.05 ” with “ 2.05(a) ”.

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(d) Section 2.01 of the Credit Agreement is hereby amended to add the following as new subsection (b):

(b) Term Loan . On the Fourth Amendment Effective Date, the Lenders severally agree to make a term loan (the “ Term Loan ”) in the aggregate amount equal to the amount of such Lender’s portion of the Term Loan Principal Amount as set forth on Schedule 2.01(b) . The Term Loan shall be deemed to be made as of the Fourth Amendment Effective Date in order to repay the amount of the Revolving Loan that exceeds the Borrowing Base in effect as of the Fourth Amendment Effective Date. Amounts borrowed under this Section 2.01(b) which are repaid or prepaid may not be reborrowed.

(e) The heading to Section 2.02 and Section 2.02(a) of the Credit Agreement is hereby amended and restated in its entirety to read as follows:

2.02 Borrowings, Conversions and Continuations of Loans .

(a) Each Borrowing, each conversion of Revolving Loans from one Type to the other, and each continuation of Eurodollar Rate Loans shall be made upon Borrower’s irrevocable notice to Agent, which may be given by telephone, provided that such notice is promptly followed by facsimile notice. Each such notice, and each Term Loan Notice, must be received by Agent not later than 11:00 a.m., Central Time, (i) three Business Days prior to the requested date of any Borrowing of, conversion to or continuation of Eurodollar Rate Loans or of any conversion of Eurodollar Rate Loans to Base Rate Loans, and (ii) on the requested date of any Borrowing of Base Rate Loans. Each telephonic notice by Borrower pursuant to this Section 2.02(a) with respect to Loans must be confirmed promptly by delivery to Agent of a written Revolving Loan Notice or Term Loan Notice, as applicable, appropriately completed and signed by a Responsible Officer of Borrower. With respect to Revolving Loans, each Borrowing of, conversion to or continuation of Eurodollar Rate Loans shall be in a principal amount of $500,000 or a greater integral multiple of $100,000. Each Borrowing of or conversion to Base Rate Loans shall be in a principal amount of $100,000 or a greater integral multiple of $100,000. Each Revolving Loan Notice (whether telephonic or written) shall specify (i) whether Borrower is requesting a Borrowing, a conversion of Revolving Loans from one Type to the other, or a continuation of Revolving Loans that are Eurodollar Rate Loans, (ii) the requested date of the Borrowing, conversion or continuation, as the case may be (which shall be a Business Day), (iii) the principal amount of Revolving Loans to be borrowed, converted or continued, (iv) the Type of Revolving Loans to be borrowed or to which existing Revolving Loans are to be converted, and (v) if applicable, the duration of the Interest Period with respect thereto. With respect to Revolving Loans, if Borrower fails to specify a Type of Revolving Loan in a Revolving Loan Notice or if

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Borrower fails to give a timely notice requesting a conversion or continuation, then the applicable Revolving Loans shall be made, or converted to, Base Rate Loans. Any such automatic conversion to Base Rate Loans shall be effective as of the last day of the Interest Period then in effect with respect to the applicable Eurodollar Rate Loans. If Borrower requests a Borrowing of, conversion to, or continuation of Revolving Loans that are Eurodollar Rate Loans in any such Revolving Loan Notice, but fails to specify an Interest Period, it will be deemed to have specified an Interest Period of one month. The Term Loan shall initially be made (without the Borrower being required to submit a Term Loan Notice) as a Eurodollar Rate Loan having an Interest Period of one month. The Term Loan shall be automatically continued (without the Borrower being required to submit a Term Loan Notice) as a Eurodollar Rate Loan having an Interest Period of one month on the last day of the immediately preceding Interest Period, unless otherwise specified in a Term Loan Notice delivered to the Agent. Each Term Loan Notice (whether telephonic or written) shall specify (i) whether Borrower is requesting a conversion of the Term Loan from one Type to the other, or a continuation of the Term Loan as a Eurodollar Rate Loan, (ii) the requested date of the conversion or continuation, as the case may be (which shall be a Business Day), and (iii) if applicable, the duration of the Interest Period with respect thereto.

(f) Section 2.02(e) of the Credit Agreement is hereby amended to add the following sentence to the end of such subsection:

Only one Interest Period shall be in effect with respect to the Term Loan.

(g) Section 2.05 of the Credit Agreement is hereby amended and restated in its entirety to read as follows:

2.05 Prepayments:

(a) Optional . Borrower may, upon notice to Agent, at any time or from time to time voluntarily prepay Loans in whole or in part without premium or penalty; provided that (i) such notice must be received by Agent not later than 11:00 a.m., Central Time, (A) five Business Days prior to any date of