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                                                                    EXHIBIT 10.1


                                SECOND AMENDMENT

                  SECOND AMENDMENT, dated as of December 13, 2002 (this
"Amendment"), to the Amended and Restated Credit Agreement, dated as of May 17,
2002 (as amended to the date hereof, the "Credit Agreement"), among TESORO
PETROLEUM CORPORATION, a Delaware corporation (the "Borrower"), the several
banks and financial institutions or entities party thereto (each a "Lender" and,
collectively, the "Lenders"), LEHMAN BROTHERS INC., as advisor, lead arranger
and book manager (in such capacity, the "Arranger"), LEHMAN COMMERCIAL PAPER
INC., as syndication agent (in such capacity, the "Syndication Agent"), ABN AMRO
BANK N.V., CREDIT LYONNAIS NEW YORK BRANCH and THE BANK OF NOVA SCOTIA, as
co-documentation agents (in such capacity, the "Co-Documentation Agents") and
BANK ONE, NA, as administrative agent (in such capacity, the "Administrative
Agent"). Unless otherwise defined herein, capitalized terms which are defined in
the Credit Agreement are used herein as defined therein.


                                   WITNESSETH:


                  WHEREAS, the Borrower has requested the Lenders to consent to
amendments to certain provisions of the Credit Agreement; and

                  WHEREAS, the Lenders are willing to consent to the requested
amendments, on and subject to the terms and conditions contained herein;

                  NOW THEREFORE, in consideration of the premises and the
agreements hereinafter set forth, the parties hereto hereby agree as follows:

                  I. Defined Terms. Unless otherwise defined herein, terms
defined in the Credit Agreement and used herein shall have the meanings given to
them in the Credit Agreement.

                  II. Amendments to Credit Agreement.

                  1. Amendments to Section 6.12(a). Section 6.12(a) of the
Credit Agreement is by hereby amended as follows:

                  (a) By replacing "$175,000,000" in clause (i) of the first
sentence of such Section with "$167,000,000".

                  (b) By adding the following parenthetical at the end of clause
(i) of the first sentence of such Section:



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                  (provided that the aggregate amount of Net Cash Proceeds
                  required to be generated pursuant to this clause (i) shall be
                  reduced dollar-for-dollar to the extent the aggregate sale
                  price for the sale of the Beacon retail sites is less than
                  $67,000,000 as a result of the valuation of the inventory at
                  such sites on the sale date being less than the originally
                  estimated amount of $5,000,000)

                  (c) By replacing the parenthetical clause at the end of the
first sentence of such Section with the following:

                  (including the Net Cash Proceeds received on or before
                  December 31, 2002 (or, if such deadline shall have been
                  extended to February 15, 2003 pursuant to the last sentence of
                  this Section, on or before February 15, 2003) pursuant to the
                  foregoing clause (i))

                  (d) By adding the following sentence at the end of such
Section:

                  Notwithstanding the foregoing provisions of this Section
                  6.12(a), (I) if the Borrower shall have received less than
                  $175,000,000 of Net Cash Proceeds pursuant to clause (i) of
                  this Section 6.12(a) on or prior to December 31, 2002, then,
                  unless clause (II) below is applicable, the Borrower, in
                  addition to applying such Net Cash Proceeds to the prepayment
                  of the Loans as required by clause (A) above, shall prepay the
                  Term Loans on or prior to December 31, 2002 in an additional
                  amount such that the aggregate amount of Term Loans prepaid
                  since the First Amendment Effective Date is at least
                  $87,500,000; and (II) if the Borrower shall not have received
                  at least $167,000,000 of Net Cash Proceeds pursuant to clause
                  (i) of this Section 6.12(a) (or such lesser amount as is
                  required pursuant to the proviso to such clause) on or prior
                  to December 31, 2002, the December 31, 2002 deadline referred
                  to in clause (i) of this Section 6.12(a) shall be deemed on
                  such date to be extended to February 15, 2003 provided that,
                  by 5 p.m. Chicago time on January 2, 2003, the Borrower shall
                  have paid to the Administrative Agent, for the account of each
                  Lender, a fee for such extension in an amount equal to 0.10%
                  of the Aggregate Exposure of such Lender.

                  III. Conditions to Effectiveness. This Amendment shall become
effective on the date (the "Amendment Effective Date") on which all of the
following conditions precedent have been satisfied or waived:

                  1. The Administrative Agent shall have received a counterpart
hereof duly executed and delivered by Borrower.

                  2. The Administrative Agent shall have received written
consents to the execution of this Amendment ("Lender Consent Letters") from
Lenders constituting the Required Lenders.

                  3. The Administrative Agent shall have received an executed
Acknowledgment and Consent, in the form set forth at the end of this Amendment,
from each


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Loan Party other than the Borrower (such Acknowledgements and Consents, together
with this Amendment, the "Amendment Documents").

                  4. The Administrative Agent shall have received, for the
account of each Lender that executes and delivers a Lender Consent Letter on or
prior to 5 p.m. Chicago time on December 13, 2002, an amendment fee in an amount
equal to 0.05% of the Aggregate Exposure of such Lender.

                  IV. General.

                  1. Representation and Warranties. To induce the Administrative
Agent to enter into this Amendment and to induce the Lenders to consent thereto,
the Borrower hereby represents and warrants to the Agents and all of the Lenders
as of the Amendment Effective Date that:

                  (a) Each Loan Party has the corporate power and authority, and
the legal right, to make and deliver the Amendment Documents to which it is a
party and to perform the Loan Documents to which it is a party, as amended by
the Amendment Documents, and has taken all necessary corporate action to
authorize the execution, delivery and performance of such Amendment Documents
and the performance of such Loan Documents, as so amended.

                  (b) No consent or authorization of, approval by, notice to,
filing with or other act by or in respect of, any Governmental Authority or any
other Person is required in connection with the execution and delivery of the
Amendment Documents or with the performance, validity or enforceability of the
Loan Documents, as amended by the Amendment Documents.

                  (c) Each Amendment Document has been duly executed and
delivered on behalf of each Loan Party which is a party thereto.

                  (d) Each Amendment Document and each Loan Document, as amended
by the Amendment Documents, constitutes a legal, valid and binding obligation of
each Loan Party which is a party thereto enforceable against such Loan Party in
accordance with its terms, except as affected by bankruptcy, insolvency,
fraudulent conveyance, reorganization, moratorium and other similar laws
relating to or affecting the enforcement of creditors' rights generally, general
equitable principles (whether considered in a proceeding in equity or at law)
and an implied covenant of good faith and fair dealing.

                  (e) The execution, delivery and performance of the Amendment
Documents and the performance of the Loan Documents, as amended by the Amendment
Documents, will not violate any Requirement of Law or Contractual Obligation of
any Loan Party which is a party thereto or of any of its Subsidiaries and will
not result in, or require, the creation or imposition of any Lien on any of its
or their respective properties or revenues pursuant to any such Requirement of
Law or Contractual Obligation.

                  (f) The representations and warranties made by the Loan
Parties in the Loan Documents are true and correct in all material respects on
and as of the Amendment Effective Date, after giving effect to the effectiveness
of this Amendment, as if made on and as of the Amendment Effective Date.


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                  2. Payment of Expenses. The Borrower agrees to pay or
reimburse the Administrative Agent and the Syndication Agent for all of their
reasonable out-of-pocket costs and expenses incurred in connection with the
Amendment Documents, any other documents prepared in connection herewith and the
transactions contemplated hereby, including, without limitation, the reasonable
fees and disbursements of counsel to the Administrative Agent and the
Syndication Agent.

                  3. No Other Amendments; Confirmation. Except as expressly
amended, modified and supplemented hereby, the provisions of the Loan Documents
are and shall remain in full force and effect.

                  4. GOVERNING LAW; COUNTERPARTS. (a) THIS AMENDMENT AND THE
RIGHTS AND OBLIGATIONS OF THE PARTIES HERETO SHALL BE GOVERNED BY AND CONSTRUED
IN ACCORDANCE WITH THE LAW OF THE STATE OF NEW YORK.

                  (b) This Amendment may be executed by one or more of the
parties to this Agreement on any number of separate counterparts, and all of
said counterparts taken together shall be deemed to constitute one and the same
instrument. A set of the copies of this Amendment, the Acknowledgment and
Consent and the Lender Consent Letters signed by all the parties shall be lodged
with the Borrower and the Administrative Agent. This Amendment may be delivered
by facsimile transmission of the relevant signature pages hereof.



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                  IN WITNESS WHEREOF, the parties hereto have caused this
Amendment to be duly executed and delivered by their respective proper and duly
authorized officers as of the day and year first above written.

                                       TESORO PETROLEUM CORPORATION


                                       By: /s/ G. Scott Spondlove
                                          --------------------------------------
                                          Name:  G. Scott Spondlove
                                          Title: Vice President, Finance

                                       BANK ONE, NA, as Administrative Agent


                                       By: /s/ Thomas E. Both
                                          --------------------------------------
                                          Name:  Thomas E. Both
                                          Title: Director, Capital Markets



                                Second Amendment