Brian Urlacher’s one-handed interception was headed to the highlight reel as soon as he tumbled to the ground after somehow batting the ball to himself.

Urlacher’s stellar play symbolized what kind of afternoon it was for the refreshed and still unbeaten Chicago Bears – and how frustrating the day was for the San Francisco 49ers.

Wearing bright orange uniforms and showing their speed on defense and special teams, the Bears overwhelmed the 49ers from the outset. They jumped to a 24-0 first-quarter lead and 41-0 halftime cushion before coasting to a 41-10 victory Sunday.

At 7-0, Chicago is off to its best start since the 1985 Super Bowl champions won their first 12 games.

“It was amazing. Twenty-four points in the first quarter? That’s pretty impressive, especially in this league. It doesn’t happen a lot,” said Rex Grossman, who rebounded from his poorest performance to throw three TD passes.

Urlacher’s acrobatic interception, in which he batted Alex Smith’s pass and then caught it with one hand as he was being knocked down by the 49ers Justin Smiley, was one of four turnovers the Bears generated in the first half. All four led to touchdowns.

Urlacher’s play came on the heels of a national sports magazine survey of NFL players in which he was rated the second-most overrated player to Terrell Owens.

Asked if he had any reaction to the poll, last year’s NFL Defensive Player of the Year said: “No, I don’t. Watch the film. I don’t know what people are saying. All I can do is go out there and play hard and try to help my team win.”

Grossman rebounded from a four-interception, two-fumble performance in a narrow 24-23 win at Arizona before a bye week to complete 23 of 29 passes for 252 yards against the 49ers’ woeful pass defense.

“I’m just glad I went out and did what the coaches asked me to do, respond from having a poor game and learn from some of the mistakes I made and continue to get better,” Grossman said.

The 24 first-quarter points set a franchise record for the opening period and the 41 in the first half tied a mark set in 1948 against Washington.

“At halftime you just think to yourself, `How did it get out of control so fast?’” said 49ers defensive lineman Bryant Young. “It happened so fast we were just trying to find a way to get it resolved. ... We have to give ourselves a chance.”

San Francisco averted a shutout in the fourth quarter on a 23-yard field goal by Joe Nedney and a 16-yard TD pass from Smith to Antonio Bryant.

Six plays after Urlacher’s interception, Grossman’s 5-yard TD pass to Muhsin Muhammad made it 17-0 and the Bears were on their way.

How good are they?

“No one expects us to do what we do. No one wants to give us any credit,” Urlacher said. “Everyone wants to say they didn’t play well. There’s a reason they didn’t play well.”

Smith was stripped of the ball in the 49ers’ next series, and Tommie Harris picked it up and ran to San Francisco’s 13. That set up a 1-yard TD by Cedric Benson and a 24-0 lead with a minute to go in the opening quarter.

“Hopefully I will never have to deal with a halftime coming in 41-0 like that,” Smith said. “We talked about it all week. This is a team that feeds off turnovers, a team that strives off turnovers.”

The Bears had such a comfortable lead they went on fourth down from the San Francisco 1 early in the second quarter. Grossman lofted a TD pass to Desmond Clark.

After the Bears took an early 3-0 lead, the 49ers Maurice Hicks fumbled the ensuing kickoff and Cameron Worrell recovered at the 15, leading to a 7-yard TD run by Thomas Jones.

San Francisco entered giving up 32 points a game, but the defense wasn’t to fault early on because turnovers allowed the Bears to work from short fields. Drives started at the 15, 41 and 13, and they turned all three into touchdowns to take the big opening-quarter lead.

The 49ers coughed up the ball a fourth time late in the half when Bryant caught a pass and fumbled, with Ricky Manning Jr. recovering.

Instead of running out the clock, the Bears capitalized again. Grossman’s 27-yard TD pass to a wide-open Clark with 10 seconds left, which completed a quick four-play, 70-yard drive in just 62 seconds.