SAN FRANCISCO – Vernon Davis' assessment of the Bears' defensive line evidently reached Chicago.

During pregame warmups, Bears defensive end Adewale Ogunleye approached Davis and got in his face. The two exchanged a few heated words before Bears center Olin Kreutz entered the conversation and pulled Ogunleye away.

Davis, of course, called out the Chicago defensive line earlier in the week by saying the 49ers would "destroy" the Chicago front. But Ogunleye was the one Bears defensive lineman Davis said he respected.

Davis after the game: "They were trying to hit me, bump me and hit me when I wasn't looking. They were trying to bang me around a little bit."

Davis on the pregame exchange with Ogunleye: "I said something to him. He didn't say nothing to me. I said that to get my team fired up. I just told him to get ready because we're coming at 'em. We're coming. He said, 'Watch out because we're coming and we ain't scared of you.' "

Davis had a nice play in the first quarter in which he caught a short crossing route and ran over linebacker Nick Roach on his way to a six-yard gain.

But it was another tight end, Greg Olsen, who dominated the first half. Olsen had five catches for 55 yards in the opening period and finished with seven catches for 75 yards.

Veteran's day off – Wide receiver Isaac Bruce was inactive for the first time since joining the 49ers last season. Bruce sprained his ankle Oct. 4 in a game against the Rams and, according to the team, rolled the same ankle in Tuesday's closed practice.

With the 16-year veteran out of the lineup, the 49ers were decidedly younger at the position. The starters were a rookie, Michael Crabtree, and a second-year player, Josh Morgan. Third-year player Jason Hill filled in for Bruce.

Alex Smith targeted Crabtree on four of his first five passes.

The 49ers' first offensive play of the game was a 25-yard toss to Crabtree along the sideline. The rookie hauled it in with one hand, but the officials ruled he was out of bounds. The ruling was upheld on a replay challenge.

Later on the drive, Crabtree dropped a pass deep in Bears territory. Later in the half, a deep pass to Crabtree was intercepted by cornerback Zackary Bowman. Crabtree finished with four catches for 48 yards.

Pick of the day – Nose tackle Aubrayo Franklin's first career interception saved a touchdown while cornerback Tarell Brown's first this season set up the 49ers' first score.

After driving deep into San Francisco territory, the Bears seemed guaranteed of at least a field goal. But on third and goal, quarterback Jay Cutler's pass to tight end Kellen Davis was picked off at the goal line by the 317-pound Franklin, who returned it to the San Francisco 11.

Another Cutler pass, this one to Devin Hester, was intercepted by Brown when Hester slipped on the play. Brown returned it 51 yards to the Chicago 14-yard line. On the next play, Frank Gore scored the first touchdown of the game.

Safety Dashon Goldson also intercepted Cutler, Goldson's second interception of the season.

Et cetera – Agent Drew Rosenhaus was on the sideline for Thursday's nationally televised game. Rodenhaus has several clients on both teams, including Gore and Hill.

• Rookie linebacker Diyral Briggs, who spent the first part of the season on the practice squad, was in uniform for the first time this year.

• Linebacker Takeo Spikes strained his hamstring on a long catch and run by Bears running back Matt Forte in the first half and did not return. Rookie Scott McKillop and Matt Wilhelm filled in.

Read Matthew Barrows' archives and blogs at www.sacbee.com/sf49ers.