SAN ANTONIO, TX – MARCH 11: Tim Duncan #21 of the San Antonio Spurs rebounds against the Oklahoma City Thunder on March 11, 2013 at the AT&T Center in San Antonio, Texas. NOTE TO USER: User expressly acknowledges and agrees that, by downloading and/or using this Photograph, user is consenting to the terms and conditions of the Getty Images License Agreement. Mandatory Copyright Notice: Copyright 2013 NBAE (Photo by Garrett W. Ellwood/NBAE via Getty Images)