SAN FRANCISCO (AP) - Colin Kaepernick tossed a touchdown pass to Vernon Davis, Kendall Hunter ran for a score and the San Francisco 49ers led the Chicago Bears 17-0 early in the second quarter on Monday night.
Kaepernick completed 8 of 9 passes for 126 yards in the first period and looked calm and in control early in his first NFL start. With Alex Smith out with a concussion, he also led San Francisco downfield on its first possession before David Akers kicked a 32-yard field goal.
The former Nevada quarterback led the Battle of the Backups at the start.
Jason Campbell also started for the Bears with Jay Cutler out with a concussion. Campbell completed 1 of 3 passes, and Matt Forte ran 22 yards on six carries as Chicago struggled to get any offensive momentum.
The 49ers seemed to have no problem with a fill-in starter. Hunter added a 14-yard touchdown run early in the second quarter to extend the lead to 17-0.
Late Monday morning, the 49ers announced Smith failed to pass the NFL's concussion treatment protocol. Team medical director Dr. Dan Garza evaluated Smith, who was hurt eight days ago against St. Louis. Smith had made 28 consecutive starts.
Kaepernick, who replaced Smith midway through the second quarter in the 24-24 tie against the Rams, finally got to show his stuff in primetime after San Francisco drafted him in the second round last year.
Kaepernick completed his first four passes, including a pair to Davis, on San Francisco's opening drive. The 49ers also were helped by a 15-yard personal foul penalty for a late hit by Chris Conte after Mario Manningham's 8-yard catch.
Kaepernick still missed Davis running free in the end zone on third-and-1 from the Bears 14 for his first incompletion, and San Francisco settled for the field goal by Akers.
Kaepernick connected with Kyle Williams for 57 yards, dropping the ball over two defenders and hitting the receiver in stride down the sideline. On the next play, Davis caught a 3-yard pass to put the 49ers ahead 10-0, shooting the ball over the crossbar in celebration.
Forte ran for 8 yards on two carries before Aldon Smith sacked Campbell to end Chicago's first possession in a hurry, and the Bears failed to cross midfield on its second drive. Smith leads the 49ers with 10 1/2 sacks.
Campbell, who missed the final 10 games with the Oakland Raiders last season with a broken collarbone, started for the Bears for the first time.
Along with Smith out, San Francisco got another scare when coach Jim Harbaugh missed most of Thursday's practice to undergo a minor procedure for an irregular heartbeat. He returned Friday, energized and eager to get back to work.
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