UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549


                                    FORM 8-K

                                 CURRENT REPORT
     Pursuant to Section 13 or 15(D) of The Securities Exchange Act of 1934

Date of Report (Date of earliest event reported) April 20, 2006 (April 20, 2006)

                                AZTAR CORPORATION
             (Exact name of registrant as specified in its charter)


              Delaware                     1-5440               86-0636534
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  (State or other jurisdiction of       (Commission           (IRS Employer
           incorporation)               File Number)       Identification No.)


               2390 Camelback Road, Suite 400
                      Phoenix, Arizona                       85016
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          (Address of principal executive offices)         (Zip Code)


Registrant's telephone number, including area code   (602) 381-4100
                                                   -----------------------------


                                    (Former name or former address, if changed
since last report.)

Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions (see General Instruction A.2. below):

[ ]  Written communications pursuant to Rule 425 under the Securities Act
     (17 CFR 230.425)

[ ]  Soliciting material pursuant to Rule 14a-12 under the Exchange Act
     (17 CFR 240.14a-12)

[ ]  Pre-commencement communications pursuant to Rule 14d-2(b) under the
     Exchange Act (17 CFR 240.14d-2(b))

[ ]  Pre-commencement communications pursuant to Rule 13e-4(c) under the
     Exchange Act (17 CFR 240.13e-4(c))



Item 3.03.        Material Modification to Rights of Security Holders


         In order to give effect to an amendment, dated as of April 18, 2006, to
the Agreement and Plan of Merger, dated as of March 13, 2006 (the "Merger
Agreement"), among Aztar Corporation (the "Company"), Pinnacle Entertainment,
Inc. ("Pinnacle") and PNK Development 1, Inc., on April 20, 2006, the Company
and Mellon Investor Services LLC (as successor to ChaseMellon Shareholder
Services, L.L.C.) executed Amendment No. 2 ("Amendment No. 2") to the Rights
Agreement, dated as of December 14, 1999, and amended as of March 14, 2006 (the
"Rights Agreement"), between the Company and ChaseMellon Shareholder Services,
L.L.C., as rights agent.


         Capitalized terms used below but not defined herein shall have the
meanings assigned thereto in the Rights Agreement. Amendment No. 2 provides that
neither Pinnacle nor any of its subsidiaries shall be deemed an Acquiring Person
(x) by virtue of their acquisition, or their right to acquire, beneficial
ownership of Common Stock of the Company as a result of their execution of the
Merger Agreement (after giving effect to any amendment to the Merger Agreement),
(y) the consummation of the Merger, or (z) any other transaction contemplated by
the Merger.

         The Rights Agreement is filed as Exhibit 1 to the Company's
Registration Statement on Form 8-A, filed with the Securities and Exchange
Commission (the "Commission") on December 15, 1999 and is incorporated herein by
reference. Amendment No. 1 to the Rights Agreement ("Amendment No. 1") is filed
as Exhibit 4.2 to the Current Report on Form 8-K, filed by the Company with the
Commission on March 16, 2006, and is incorporated herein by reference. Amendment
No. 2 is attached as Exhibit 4.3 hereto and is incorporated herein by reference.
The foregoing description of the Rights Agreement, Amendment No. 1 and Amendment
No. 2 does not purport to be complete and is qualified in its entirety by
reference to such exhibits.

Item 9.01.        Financial Statements and Exhibits.

         (c)      Exhibits

         4.1                Rights Agreement, dated as of December 14, 1999,
                            between Aztar Corporation and ChaseMellon
                            Shareholder Services, L.L.C., as Rights Agent, filed
                            as Exhibit 1 to Aztar's Corporation's Registration
                            Statement on Form 8-A, filed by Aztar Corporation on
                            December 15, 1999, and incorporated herein by
                            reference.

         4.2                Amendment No. 1, dated as of March 14, 2006, to the
                            Rights Agreement, by and between Aztar Corporation
                            and Mellon Investor Services LLC (as successor to
                            ChaseMellon Shareholder Services, L.L.C.), as Rights
                            Agent, filed as Exhibit 4.2 to Current Report on
                            Form 8-K, filed by Aztar Corporation on March 16,
                            2006, and incorporated herein by reference.

         4.3                Amendment No. 2, dated as of April 20, 2006, to the
                            Rights Agreement, by and between Aztar Corporation
                            and Mellon Investor Services LLC (as successor to
                            ChaseMellon Shareholder Services, L.L.C.), as Rights
                            Agent.



                                   SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.



                                       AZTAR CORPORATION


                                       By: /s/ Neil A. Ciarfalia
                                           ------------------------------------
                                           Name:  Neil A. Ciarfalia
                                           Title: Chief Financial Officer,
                                                  Vice President and Treasurer

Date: April 20, 2006



                                  EXHIBIT INDEX

        Exhibit No.           Description
        -----------           -----------

         4.1                Rights Agreement, dated as of December 14, 1999,
                            between Aztar Corporation and ChaseMellon
                            Shareholder Services, L.L.C., as Rights Agent, filed
                            as Exhibit 1 to Aztar's Corporation's Registration
                            Statement on Form 8-A, filed by Aztar Corporation on
                            December 15, 1999, and incorporated herein by
                            reference.

         4.2                Amendment No. 1, dated as of March 14, 2006, to the
                            Rights Agreement, by and between Aztar Corporation
                            and Mellon Investor Services LLC (as successor to
                            ChaseMellon Shareholder Services, L.L.C.), as Rights
                            Agent, filed as Exhibit 4.2 to Current Report on
                            Form 8-K, filed by Aztar Corporation on March 16,
                            2006, and incorporated herein by reference.

         4.3                Amendment No. 2, dated as of April 20, 2006, to the
                            Rights Agreement, by and between Aztar Corporation
                            and Mellon Investor Services LLC (as successor to
                            ChaseMellon Shareholder Services, L.L.C.), as Rights
                            Agent.