Exhibit 10.2

EXECUTION COPY

SIXTH AMENDMENT

TO

SECOND AMENDED AND RESTATED

SENIOR REVOLVING CREDIT AGREEMENT

among

PETROHAWK ENERGY CORPORATION,

as the Borrower,

BNP PARIBAS,

as Administrative Agent,

BANK OF AMERICA, N.A. and

BMO CAPITAL MARKETS FINANCING, INC.,

as Co-Syndication Agents,

JPMORGAN CHASE BANK, N.A.,

WELLS FARGO BANK, N.A. and

FORTIS CAPITAL CORP.

as Co-Documentation Agents,

and

THE LENDERS PARTY HERETO

Effective as of May 5, 2008

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SIXTH AMENDMENT TO

SECOND AMENDED AND RESTATED SENIOR REVOLVING CREDIT AGREEMENT

This SIXTH AMENDMENT TO SECOND AMENDED AND RESTATED SENIOR REVOLVING CREDIT
AGREEMENT (this “Sixth Amendment”) executed effective as of May 5, 2008 (the
“Sixth Amendment Effective Date”) is among PETROHAWK ENERGY CORPORATION, a
corporation duly formed and existing under the laws of the State of Delaware
(the “Borrower”); each of the Guarantors signatory hereto (the “Guarantors”);
each of the Lenders from time to time party hereto; BNP PARIBAS (in its
individual capacity, “BNP Paribas”), as administrative agent for the Lenders (in
such capacity, together with its successors in such capacity, the
“Administrative Agent”); Bank of America, N.A. and BMO Capital Markets
Financing, Inc., as co-syndication agents for the Lenders (in such capacity,
together with their successors in such capacity, the “Co-Syndication Agents”);
and JPMorgan Chase Bank, N.A., Wells Fargo Bank, N.A. and Fortis Capital Corp.
as co-documentation agents for the Lenders (in such capacity, together with
their successors in such capacity, the “Co-Documentation Agents”).

Recitals

A. The Borrower, the Administrative Agent, the other Agents and Lenders named
and defined therein as lenders and agents, are parties to that certain Second
Amended and Restated Senior Revolving Credit Agreement dated as of July 12,
2006, as amended by the First Amendment to Second Amended and Restated Senior
Revolving Credit Agreement, dated as of July 24, 2006, the Second Amendment to
Second Amended and Restated Senior Revolving Credit Agreement, dated as of
May 8, 2007, the Third Amendment to Second Amended and Restated Senior Revolving
Credit Agreement, dated as of July 25, 2007, the Fourth Amendment to Second
Amended and Restated Senior Revolving Credit Agreement, dated as of October 15,
2007 and the Fifth Amendment to Second Amended and Restated Senior Revolving
Credit Agreement, dated as of February 5, 2008, pursuant to which such lenders
and agents provided certain loans and extensions of credit to the Borrower (as
amended, the “Credit Agreement”).

B. The Administrative Agent has requested, and the Borrower, the Administrative
Agent, the Co-Syndication Agents, the Co-Documentation Agents and Lenders have
agreed to amend certain provisions of the Credit Agreement.

C. NOW, THEREFORE, in consideration of the premises and the mutual covenants
herein contained, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto agree as
follows:

Section 1. Defined Terms. Each capitalized term which is defined in the Credit
Agreement, but which is not defined in this Sixth Amendment, shall have the
meaning ascribed such term in the Credit Agreement. Unless otherwise indicated,
all section references in this Sixth Amendment refer to sections in the Credit
Agreement.

Section 2. Amendments to Credit Agreement.

2.1 Certain Defined Terms. The following defined terms in Section 1.02 are
hereby amended and restated, or added, in their entirety as follows:

 

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“Agreement” means this Second Amended and Restated Senior Revolving Credit
Agreement, as amended by the First Amendment to Second Amended and Restated
Senior Revolving Credit Agreement, dated as of July 24, 2006, the Second
Amendment to Second Amended and Restated Senior Revolving Credit Agreement,
dated as of May 8, 2007, the Third Amendment to Second Amended and Restated
Senior Revolving Credit Agreement dated as of July 25, 2007, the Fourth
Amendment to Second Amended and Restated Senior Revolving Credit Agreement,
dated as of October 15, 2007, the Fifth Amendment to Second Amended and Restated
Senior Revolving Credit Agreement dated as of February 5, 2008 and the Sixth
Amendment to Second Amended and Restated Senior Revolving Credit Agreement dated
as of May 5, 2008, as the same may from time to time be further amended,
modified, supplemented or restated.

“Current Production” means, for each month, the lesser of (a) the prior month’s
production of each of crude oil and natural gas, calculated separately, of the
Borrower and its Restricted Subsidiaries and (b) the internally forecasted
production of each of crude oil and natural gas, calculated separately, of the
Borrower and its Restricted Subsidiaries for each month for the next 48 months.

“Senior Notes” means any unsecured senior or senior subordinated notes issued by
the Borrower under Section 9.02(l) and any guarantees thereof by the Borrower or
a Guarantor.

2.2 Section 2.07.

Section 2.07(a) is hereby amended by inserting “Section 2.07(e),” before
“Section 8.13(c)” in the second sentence.

Section 2.07 is hereby amended by adding the following Section 2.07(e) after
Section 2.07(d):

“(e) Reduction of Borrowing Base Upon Issuance of Permitted Senior Notes.
Notwithstanding anything to the contrary contained herein, upon the issuance of
any Senior Notes in accordance with Section 9.02(l), the Borrowing Base then in
effect shall be reduced by an amount equal to the product of 0.25 multiplied by
the stated principal amount of such Senior Notes (without regard to any initial
issue discount), and the Borrowing Base as so reduced shall become the new
Borrowing Base immediately upon the date of such issuance, effective and
applicable to the Borrower, the Agents, the Issuing Bank and the Lenders on such
date until the next redetermination or modification thereof hereunder.”

2.3 Section 8.01. Section 8.01 is hereby amended by adding the following
subsection (t):

“(t) Monthly Production Report. Promptly after preparation but no later than 15
days after the end of each calendar month, a report from the Borrower in form
and substance satisfactory to the Administrative Agent setting forth the
previous

 

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month’s production of each of crude oil and natural gas, each calculated
separately. With each such report, the Borrower shall either (i) certify,
represent and warrant that the internally forecasted production from the Oil and
Gas Properties of the Borrower and the Restricted Subsidiaries for all months in
which the Borrower or one of its Restricted Subsidiaries has Swap Agreements
equals or exceeds their prior month’s production of each of crude oil and
natural gas, calculated separately, or (ii) deliver an additional detailed
forecasted production of each of crude oil and natural gas, calculated
separately, for the next 48 months.”

2.4 Section 9.02. Section 9.02 is hereby amended by adding the following
Section 9.02(l) after Section 9.02(k):

“(l) Senior Notes provided that (1) at the time of incurring such Debt (a) no
Default has occurred and is then continuing and (b) no Default would result from
the incurrence of such Debt after giving effect to the incurrence of such Debt
(and any concurrent repayment of Debt with the proceeds of such incurrence),
(2) such Debt does not have any scheduled amortization prior to one year after
the Maturity Date, (3) such Debt does not mature sooner than one year after the
Maturity Date, (4) the terms of such Debt are not materially more onerous, taken
as a whole, than the terms of this Agreement and the other Loan Documents and
(5) such Debt and any guarantees thereof are on prevailing market terms for
similar situated companies.”

2.5 Section 9.19. Section 9.19 is hereby amended and restated in its entirety as
follows:

“Section 9.19 Swap Agreements. The Borrower will not, and will not permit any
Restricted Subsidiary to, enter into any Swap Agreements with any Person other
than (a) Swap Agreements in respect of commodities (i) with an Approved
Counterparty and (ii) the notional volumes for which (when aggregated with other
commodity Swap Agreements then in effect other than basis differential swaps on
volumes already hedged pursuant to other Swap Agreements) do not exceed, as of
the date such Swap Agreement is executed and at any time thereafter, (A) 100% of
the Current Production for each month during the period during which such Swap
Agreement is in effect for each of crude oil and natural gas, calculated
separately, through the calendar year 2010; (B) 75% of the Current Production
for each month during the period during which such Swap Agreement is in effect
for each of crude oil and natural gas, calculated separately, for the calendar
year 2011; and (C) 50% of the Current Production for each month during the
period during which such Swap Agreement is in effect for each of crude oil and
natural gas, calculated separately, for the calendar year 2012, (b) Swap
Agreements in respect of interest rates with an Approved Counterparty, as
follows: (i) Swap Agreements effectively converting interest rates from fixed to
floating, the notional amounts of which (when aggregated with all other Swap
Agreements of the Borrower and its Restricted Subsidiaries then in effect
effectively converting interest rates from fixed to floating) do not exceed 50%
of the then outstanding principal amount of

 

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the Borrower’s Debt for borrowed money which bears interest at a fixed rate and
(ii) Swap Agreements effectively converting interest rates from floating to
fixed, the notional amounts of which (when aggregated with all other Swap
Agreements of the Borrower and its Restricted Subsidiaries then in effect
effectively converting interest rates from floating to fixed) do not exceed 75%
of the then outstanding principal amount of the Borrower’s Debt for borrowed
money which bears interest at a floating rate, and (c) Swap Agreements required
under Section 6.01(q). In no event shall any Swap Agreement contain any
requirement, agreement or covenant for the Borrower or any Restricted Subsidiary
to post collateral or margin to secure their obligations under such Swap
Agreement or to cover market exposures except to the extent permitted by
Section 9.03(d).”

Section 3. Waiver.

3.1 The Borrower has informed the Administrative Agent that it has entered into
Swap Agreements that exceed the 85% limit set forth in Section 9.19(a)(ii) of
the Credit Agreement. Therefore, the Majority Lenders do hereby waive
Section 9.19(a)(ii) for the fiscal quarter ending March 31, 2008, provided that
the Borrower represents and covenants, and the Borrower does hereby represent
and covenant, that after giving effect to the amendment to Section 9.19, it
would have been in compliance had such amendment been in effect for the first
fiscal quarter of 2008. Except as expressly waived herein, all covenants,
obligations and agreements of the Borrower contained in the Credit Agreement and
the other Loan Documents shall remain in full force and effect in accordance
with their terms.

3.2 Neither the execution by the Administrative Agent or the Lenders of this
Amendment, nor any other act or omission by the Administrative Agent or the
Lenders or their officers in connection herewith, shall be deemed a waiver by
the Administrative Agent or the Lenders of any other defaults which may exist,
which may have occurred prior to the Swap Agreements described in Section 3.1,
or which may occur in the future under the Credit Agreement and/or the other
Loan Documents, or any future defaults of the same provision waived hereunder
(collectively “Other Violations”). Similarly, nothing contained in this
Amendment shall directly or indirectly in any way whatsoever either: (i) impair,
prejudice or otherwise adversely affect the Administrative Agent’s or the
Lenders’ right at any time to exercise any right, privilege or remedy in
connection with the Loan Documents with respect to any Other Violations, or
(ii) constitute any course of dealing or other basis for altering any obligation
of the Borrower or any right, privilege or remedy of the Administrative Agent or
the Lenders under the Credit Agreement, the other Loan Documents, or any other
contract or instrument. Nothing in this letter shall be construed to be a
consent by the Administrative Agent or the Lenders to any Other Violations.

Section 4. Conditions Precedent. The effectiveness of this Sixth Amendment is
subject to the receipt by the Administrative Agent of the following documents
and satisfaction of the other conditions provided in this Section 4, each of
which shall be reasonably satisfactory to the Administrative Agent in form and
substance:

4.1 The Administrative Agent and the Lenders shall have received all fees and
other amounts due and payable on or prior to the Sixth Amendment Effective Date,
including, to the

 

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extent invoiced, reimbursement or payment of all out-of-pocket expenses required
to be reimbursed or paid by the Borrower hereunder.

4.2 The Administrative Agent shall have received from the Administrative Agent,
each of the Majority Lenders and each of the Guarantors, counterparts (in such
number as may be requested by the Administrative Agent) of this Sixth Amendment
signed on behalf of such Person.

4.3 No Default or Event of Default shall have occurred and be continuing as of
the Sixth Amendment Effective Date.

4.4 The Administrative Agent shall have received such other documents as the
Administrative Agent or its special counsel may reasonably require.

The Administrative Agent is hereby authorized and directed to declare this Sixth
Amendment to be effective when it has received documents confirming or
certifying, to the satisfaction of the Administrative Agent, compliance with the
conditions set forth in this Section 4 or the waiver of such conditions as
permitted hereby. Such declaration shall be final, conclusive and binding upon
all parties to the Credit Agreement for all purposes.

Section 5. Representations and Warranties; Etc. The Borrower and each Guarantor
hereby affirms: (a) that as of the date of execution and delivery of this Sixth
Amendment, and after giving effect to the transactions contemplated hereby, all
of the representations and warranties contained in each Loan Document to which
it is a party are true and correct in all material respects (unless made as of a
specific earlier date, in which case, was true as of such date); and (b) that
after giving effect to this Sixth Amendment, no Defaults exist under the Loan
Documents or will exist under the Loan Documents.

Section 6. Miscellaneous.

6.1 Confirmation. The provisions of the Credit Agreement (as amended by this
Sixth Amendment) shall remain in full force and effect in accordance with its
terms following the effectiveness of this Sixth Amendment.

6.2 Ratification and Affirmation of Borrower and Guarantors. The Borrower and
Guarantors hereby expressly (a) acknowledge the terms of this Sixth Amendment,
(b) ratify and affirm their obligations under the Loan Documents to which they
are a party, (c) acknowledge, renew and extend their continued liabilities under
the Guarantee Agreement and the other Security Instruments to which they are a
party and agree that their guarantee under the Guarantee Agreement and the other
Security Instruments to which they are a party remains in full force and effect
with respect to the Indebtedness as amended hereby.

6.3 Counterparts. This Sixth Amendment may be executed by one or more of the
parties hereto in any number of separate counterparts, and all of such
counterparts taken together shall be deemed to constitute one and the same
instrument.

6.4 No Oral Agreement. THIS WRITTEN SIXTH AMENDMENT, THE CREDIT AGREEMENT AND
THE OTHER LOAN DOCUMENTS EXECUTED IN CONNECTION

 

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HEREWITH AND THEREWITH REPRESENT THE FINAL AGREEMENT BETWEEN THE PARTIES AND MAY
NOT BE CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR UNWRITTEN ORAL
AGREEMENTS OF THE PARTIES. THERE ARE NO SUBSEQUENT ORAL AGREEMENTS BETWEEN THE
PARTIES.

6.5 Governing Law. THIS SIXTH AMENDMENT (INCLUDING, BUT NOT LIMITED TO, THE
VALIDITY AND ENFORCEABILITY HEREOF) SHALL BE GOVERNED BY, AND CONSTRUED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF TEXAS.

 

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

 

BORROWER:     PETROHAWK ENERGY CORPORATION         By:    /s/ Floyd C. Wilson  
  Name:    Floyd C. Wilson     Title:    President and Chief Executive Officer

Sixth Amendment – Second Amended and Restated Senior Revolving Credit Agreement

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GUARANTORS:     PETROHAWK OPERATING COMPANY     P-H ENERGY, LLC     RED RIVER
FIELD SERVICES, L.L.C.     PETROHAWK PROPERTIES, LP       By:   P-H Energy,
L.L.C.         Its General Partner     WINWELL RESOURCES, INC.     WSF, INC.    
KCS RESOURCES, INC.     KCS ENERGY SERVICES, INC.     MEDALLION CALIFORNIA
PROPERTIES COMPANY     PROLIQ, INC.     ONE TEC, LLC     ONE TEC OPERATING, LLC
    BISON RANCH LLC         By:   /s/ Floyd C. Wilson     Name:   Floyd C.
Wilson     Title:   President and Chief Executive Officer

Sixth Amendment – Second Amended and Restated Senior Revolving Credit Agreement

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PETROHAWK HOLDINGS, LLC By:   /s/ Connie D. Tatum   Connie D. Tatum   President

Sixth Amendment – Second Amended and Restated Senior Revolving Credit Agreement

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ADMINISTRATIVE AGENT:    

BNP PARIBAS,

as Administrative Agent and Lender

        By:    /s/ Brian M. Malone     Name:    Brian M. Malone     Title:   
Managing Director         By:    /s/ Robert Long     Name:    Robert Long    
Title:    Vice President CO-SYNDICATION AGENTS:     BANK OF AMERICA, N.A., as
Co-Syndication
Agent and Lender         By:    /s/ Jeffrey H. RathKamp     Name:    Jeffrey H.
RathKamp     Title:    Managing Director     BMO CAPITAL MARKETS FINANCING,
INC.,
as Co-Syndication Agent and Lender         By:    /s/ James V. Ducote     Name:
   James V. Ducote     Title:    Director CO-DOCUMENTATION AGENTS:     JPMORGAN
CHASE BANK, N.A., as Co-Documentation Agent and Lender         By:    /s/
Michael A. Kamauf     Name:    Michael A. Kamauf     Title:    Vice President  
 

WELLS FARGO BANK, N.A., as

Co-Documentation Agent and Lender

        By:    /s/ Scott Hodges     Name:    Scott Hodges     Title:    Vice
President

Sixth Amendment – Second Amended and Restated Senior Revolving Credit Agreement

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FORTIS CAPITAL CORP., as Co-

Documentation Agent and Lender

        By:   /s/ Scott Myatt     Name:   Scott Myatt     Title:   Vice
President         By:   /s/ Darrell Holley     Name:   Darrell Holley     Title:
  Managing Director LENDERS:     AMEGY BANK NATIONAL ASSOCIATION         By:  
/s/ W. Bryan Chapman     Name:   W. Bryan Chapman     Title:   Senior Vice
President     SUNTRUST BANK         By:   /s/ Yann Pirio     Name:   Yann Pirio
    Title:   Director

Sixth Amendment – Second Amended and Restated Senior Revolving Credit Agreement

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LENDERS:

  BANK OF TEXAS, N.A.   By:   /s/ Mari Salazar   Name:   Mari Salazar   Title:  
Vice President   U.S. BANK NATIONAL ASSOCIATION   By:   /s/ Heather A. Han  
Name:   Heather A. Han   Title:   Assistant Vice President   COMERICA BANK   By:
  /s/ Gregory D. Smith   Name:   Gregory D. Smith   Title:   Vice President  
COMPASS BANK   By:   /s/ Dorothy Marchand   Name:   Dorothy Marchand   Title:  
Senior Vice President   STERLING BANK   By:   /s/ Daniel G. Steele   Name:  
Daniel G. Steele   Title:   SVP – Energy Manager   CITIBANK, N.A.   By:   /s/
Amy Pincu   Name:   Amy Pincu   Title:   Vice President

Sixth Amendment – Second Amended and Restated Senior Revolving Credit Agreement

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LENDERS:

  ROYAL BANK OF CANADA   By:   /s/ Jay T. Sartain   Name:   Jay T. Sartain  
Title:   Authorized Signatory

Sixth Amendment – Second Amended and Restated Senior Revolving Credit Agreement

Signature Page