SAN ANTONIO — Coach Gregg Popovich has signed a contract extension with the San Antonio Spurs.

Popovich confirmed the extension with the defending NBA champions, which runs through the 2011-12 season, before the Spurs' Game 4 loss to the Los Angeles Lakers on Tuesday night.

Popovich has led the Spurs and star Tim Duncan to four NBA titles, in 1999, 2003, 2005 and 2007. Last year, the Spurs swept the Cleveland Cavaliers in four games.

Duncan last fall agreed to a two-year extension with the Spurs that will keep him in San Antonio at least through the 2011-12 season.

The Spurs' title defense is currently on the line. They are down 3-1 to the Lakers in the Western Conference finals and face elimination on Thursday night in Game 5.

Popovich became the Spurs' head coach in December 1996. He has a 632-302 (.677) regular-season record.