Overall No. 1 draft pick Alex Smith was promoted to be the San Francisco 49ers' starting quarterback on Tuesday, ascending to the job after just four games as Tim Rattay's backup. Smith will make his first NFL start on Sunday against Peyton Manning and the Indianapolis Colts at Candlestick Park. The former Utah star played in two of the 49ers' first four games, mopping up in losses to Philadelphia and Arizona. ``I feel that Alex gives us the best chance to win, and I believe he's ready,'' San Francisco coach Mike Nolan said. ``Tim has handled everything very well, but at this time in the process, I believe it's time to get Alex in the game. ... At 1-3, we didn't draft Alex to just sit him on the bench. At 1-3, I believe we need to begin to utilize him.''