Santa Clara, CA -- (Sports Network) - The San Francisco 49ers named J.T. O'Sullivan their starting quarterback Friday.

O'Sullivan, who has never started an NFL regular season game, beat out Alex Smith, the No. 1 overall pick in the 2005 NFL Draft, and career backup Shaun Hill for the job.

The California-Davis product played under the 49ers' new offensive coordinator, Mike Martz, in Detroit last season.

"The determining factor was that JT had the better command of the three," San Francisco head coach Mike Nolan told the team's Web site.

O'Sullivan was 7-of-8 for 126 yards and a touchdown in just over one quarter of action during Thursday's preseason game against the Chicago Bears.

"This is not a case of Shaun or Alex not playing well," said Nolan. "This is a case of O'Sullivan performing very well."

Smith was named the backup and Hill will be the No. 3 quarterback.