San Antonio Spurs' Tim Duncan, left, and Phoenix Suns' Amar'e Stoudemire (1) walk up court during the first half of...

San Antonio Spurs' Tim Duncan, left, and Phoenix Suns' Amar'e Stoudemire (1) walk up court during the first half of...

SAN ANTONIO - MARCH 17: Kevin Garnett #5 of the Boston Celtics plays against Tim Duncan #21 of the San Antonio Spurs at the AT&T Center on March 17, 2008 in...

...NOVEMBER 18: Dirk Nowitzki #41 of the Dallas Mavericks goes up for the lay up against Tim Duncan #21 of the San Antonio Spurs during a game at the American Airlines Center on November...

SALT LAKE CITY, UT - NOVEMBER 05: Tim Duncan #21 of the San Antonio Spurs tries to drive to the hoop against Carlos Boozer #5...

1- SAN ANTONIO - OCTOBER 16: Tim Duncan #21 of the San Antonio Spurs reacts during a preseason game against the Cleveland Cavaliers at...

San Antonio Spurs' Tim Duncan, left, and Richard Jefferson, right, ice their knees during a preseason NBA basketball game against the...

SAN ANTONIO - NOVEMBER 26: Derrick Rose #1 of the Chicago Bulls drives against Tim Duncan #21 of the San Antonio Spurs on November 26, 2008 at the AT&T Center in...

The Spurs' title chances ride on Tim Duncan's health

SAN ANTONIO - SEPTEMBER 28: Tim Duncan # 21 of the San Antonio Spurs answers media questions during NBA Media Day on September 28...

San Antonio Spurs forward Tim Duncan is seen during the team's NBA media day in San Antonio, Monday, Sept. 28, 2009...

SAN ANTONIO - SEPTEMBER 28: Tim Duncan # 21 of the San Antonio Spurs answers media questions during NBA Media Day on September 28...

1- SAN ANTONIO - MARCH 27: Tony Parker #9, Manu Ginobili #20 and Tim Duncan #21 of the San Antonio Spurs stand for the National Anthem before playing the Los Angeles...

SAN ANTONIO - APRIL 18: Forward Tim Duncan #21 of the San Antonio Spurs reacts during a 105-97 loss against the Dallas Mavericks...

David Robinson (L) Tim Duncan (C) and head coach Gregg Popovich (R) of the San Antonio Spurs watch the rest of...