SAN FRANCISCO (AP) -- Alex Smith looked sharp, good news for the San Francisco 49ers.
Brian Griese looked just as good for the Chicago Bears -- and that might be bad news for Rex Grossman.
Smith passed for 137 yards and led the 49ers to a big early lead in their 28-14 exhibition victory over the Bears on Friday night.
Frank Gore rushed for 49 yards and a touchdown, while San Francisco's first-team defense shut down Chicago's offense under Grossman. The Niners forced two first-quarter turnovers that led to 10 points, including linebacker Jeff Ulbrich's 32-yard TD return of Grossman's fumble.
The 49ers had the league's worst offense and defense last season, but they were up 17-0 when Smith left after going 16-for-21 with no interceptions in perhaps the most confident performance of his short NFL career. New receiver Antonio Bryant had five receptions for 54 yards, and Gore also caught five passes from last season's No. 1 overall draft pick.
"It was a ton of fun," said Smith, who had one touchdown pass and 11 interceptions in nine appearances last season. "I think we did good enough that we can create some confidence and some excitement."
Meanwhile, Chicago's first-team offense did nothing to erase memories of last season's bumbling unit, which was carried to the NFC North title by an outstanding defense. Grossman, who missed the first 13 regular-season games with a broken ankle, went 3-of-11 for just 47 yards while Chicago struggled to move forward.
But Griese, signed in the offseason to give provide a veteran alternative to the injury-plagued incumbent, promptly led a 75-yard scoring drive late in the first half, capped by Gabe Reid's 12-yard TD catch.
Griese did it again in the second half, guiding an 83-yard drive ending in Rashied Davis' 41-yard TD reception. Coach Lovie Smith has insisted the Bears have faith in Grossman, but Griese -- who went 6-for-7 for 134 yards -- says he wants to start in Chicago.
Keeping the athletic Alex Smith on the move with play-action and rollouts, the 49ers drove the ball with surprising ease against the defense that allowed the NFL's fewest points last season.
Smith led a 13-play scoring drive in the second quarter, pushing San Francisco 68 yards before Gore's 1-yard TD plunge. Gore got 10 carries and most of the first-team action in the latest indication he has passed Kevan Barlow, who got just one carry, on the 49ers' depth chart.
But the 49ers' defense also did its share: Mark Bradley fumbled after a short reception on the Bears' opening drive, and Walt Harris recovered. Smith moved the 49ers into scoring range with short passes, and Joe Nedney hit a 33-yard field goal.
Grossman made the Bears' next big mistake, muffing a third-down snap and then fumbling the ball straight to Ulbrich, who returned it down the Chicago sideline for his first touchdown. Grossman never got comfortable, missing two open receivers on the Bears' first drive of the second quarter.
The 49ers replaced Smith with Jesse Palmer and Shaun Hill, who scrambled for a fourth-quarter touchdown. Second-stringer Trent Dilfer got the night off.
Chicago rested running backs Cedric Benson and Thomas Jones with minor injuries in front of a half-full Candlestick Park.
Bears cornerback Nathan Vasher, whose NFL-record 108-yard return of a missed field goal ended the first half of Chicago's victory over the 49ers last season, was shaken up on a hit in the first quarter.