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                                                               EXHIBIT 10.105(a)

                              AMENDMENT NUMBER ONE
                                     to the
         Second Amended and Restated Master Loan and Security Agreement
                            dated as of June 27, 2005
                                  by and among
                        NEW CENTURY MORTGAGE CORPORATION
                             NC CAPITAL CORPORATION
                        NEW CENTURY FINANCIAL CORPORATION
                                       and
                      CITIGROUP GLOBAL MARKETS REALTY CORP.


                This AMENDMENT NUMBER ONE (this "Amendment Number One") is made
this 28th day of December, 2005, among NEW CENTURY MORTGAGE CORPORATION, having
an address at 18400 Von Karman, Suite 1000, Irvine, California 92612 ("NC
Mortgage"), NC CAPITAL CORPORATION, having an address at 18400 Von Karman, Suite
1000, Irvine, California 92612 ("NC Capital"), NEW CENTURY FINANCIAL
CORPORATION, having an address at 18400 Von Karman, Suite 1000, Irvine,
California 92612 ("NC Financial") and CITIGROUP GLOBAL MARKETS REALTY CORP.,
having an address at 390 Greenwich Street, New York, New York 10013
("Citigroup") to the SECOND AMENDED & RESTATED MASTER LOAN AND SECURITY
AGREEMENT, dated as of June 27, 2005, among NC Mortgage, NC Capital, NC
Financial and Citigroup, as amended (the "Agreement").

                                    RECITALS

                WHEREAS, the parties have agreed to amend the Agreement to
extend the Maturity Date as more expressly set forth below.

                WHEREAS, as of the date of this Amendment Number One, each of NC
Mortgage, NC Capital and NC Financial represents to Citigroup that it is in
compliance with all of the representations and warranties and all of the
affirmative and negative covenants set forth in the Agreement and the Loan
Documents.

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

                SECTION 1. Effective as of December 31, 2005, Section 1.01 of
the Agreement shall be amended by substituting "March 31, 2006" for "December
31, 2005" in the definition of "Maturity Date" thereof.

                SECTION 2. Fees and Expenses. NC Capital agrees to pay to
Citigroup all fees and out of pocket expenses incurred by Citigroup in
connection with this Amendment Number One (including all reasonable fees and out
of pocket costs and expenses of Citigroup's legal counsel incurred in connection
with this Amendment Number One), in accordance with Section 11.03(b) of the
Agreement.


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                SECTION 3. Defined Terms. Any terms capitalized but not
otherwise defined herein shall have the respective meanings set forth in the
Agreement.

                SECTION 4. Representations. In order to induce Citigroup to
execute and deliver this Amendment Number One, NC Capital, NC Mortgage and NC
Financial hereby represent to Citigroup that as of the date hereof, after giving
effect to this Amendment Number One, each of NC Capital, NC Mortgage and NC
Financial is in full compliance with all of the terms and conditions of the
Agreement and no Event of Default or material adverse change has occurred under
the Agreement.

                SECTION 5. Limited Effect. This Amendment Number One shall
become effective upon the execution hereof by the parties hereto. Except as
expressly amended and modified by this Amendment Number One, the Agreement shall
continue in full force and effect in accordance with its terms. Reference to
this Amendment Number One need not be made in the Agreement or any other
instrument or document executed in connection therewith, or in any certificate,
letter or communication issued or made pursuant to, or with respect to, the
Agreement, any reference in any of such items to the Agreement being sufficient
to refer to the Agreement as amended hereby.

                SECTION 6. GOVERNING LAW. THIS AMENDMENT NUMBER ONE SHALL BE
CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK AND THE
OBLIGATIONS, RIGHTS, AND REMEDIES OF THE PARTIES HEREUNDER SHALL BE DETERMINED
IN ACCORDANCE WITH SUCH LAWS WITHOUT REGARD TO CONFLICT OF LAWS DOCTRINE APPLIED
IN SUCH STATE (OTHER THAN SECTION 5-1401 OF THE NEW YORK GENERAL OBLIGATIONS
LAW).

                SECTION 7. Counterparts. This Amendment Number One may be
executed by each of the parties hereto on any number of separate counterparts,
each of which shall be an original and all of which taken together shall
constitute one and the same instrument.


                            [SIGNATURE PAGE FOLLOWS]


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               IN WITNESS WHEREOF, Citigroup, NC Capital, NC Mortgage and NC
Financial have caused this Amendment Number One to be executed and delivered by
their duly authorized officers as of the day and year first above written.

                                        CITIGROUP GLOBAL MARKETS REALTY CORP.


                                        By:    /s/ James Xanthos
                                               ---------------------------------
                                        Name:  James Xanthos
                                               ---------------------------------
                                        Title: Authorized Signer
                                               ---------------------------------


                                        NC CAPITAL CORPORATION


                                        By:    /s/ Kevin Cloyd
                                               ---------------------------------
                                        Name:  Kevin Cloyd
                                               ---------------------------------
                                        Title: President
                                               ---------------------------------


                                        NEW CENTURY MORTGAGE CORPORATION


                                        By:    /s/ Kevin Cloyd
                                               ---------------------------------
                                        Name:  Kevin Cloyd
                                               ---------------------------------
                                        Title: Executive Vice President
                                               ---------------------------------


                                        NEW CENTURY FINANCIAL CORPORATION


                                        By:    /s/ Kevin Cloyd
                                               ---------------------------------
                                        Name:  Kevin Cloyd
                                               ---------------------------------
                                        Title: Executive Vice President
                                               ---------------------------------