SANTA CLARA, Calif. (AP) -Mike Singletary can see it in Alex Smith's eyes, in his body language. He's a different player now. Confident. Mature. Experienced.

At all of 25, Smith has been at the top and at the very bottom during his short NFL career. There was all the hype and talk of his potential when the San Francisco 49ers chose him No. 1 overall in the 2005 NFL draft.

Three years later he had disappeared, having worked his way back from shoulder surgery only to get hurt again three days before last year's season opener. He missed all of 2008.

San Francisco's game at Indianapolis on Sunday will mark his first start since Nov. 12, 2007, and it just so happens the Colts are also the team he faced in his NFL debut back in '05.