After the game, Thomas Brown didn’t sugarcoat what happened in his first game as interim head coach of the Bears.

“I will always be direct, honest and open about the things that happened,” Brown said. “We need to implement a better game plan on both sides of the ball so we can execute better. Of course, I will continue to challenge our boys to do their best. Encourage these guys too and also demand that we continue to remain united.”

Williams completed 17 of 23 passes for 134 yards and a passer rating of 116.9 before being replaced by Tyson Bagent with 1:59 left. The rookie quarterback extended his streak without throwing an interception to 255 pass attempts, the most in history by a Bears quarterback and an NFL rookie.

The 49ers’ offense was led by tight end George Kittle, who had six receptions for 151 yards. Jauan Jennings caught seven passes for 90 yards and two touchdowns.

The 49ers opened the game with a five-play, 70-yard drive capped by Purdy’s 7-yard touchdown pass to Jennings to give San Francisco a 7-0 lead. Purdy completed 4 of 4 passes for 70 yards on the 5-play, 70-yard drive.

The 49ers extended their lead to 14-0 on Isaac Guerendo’s 1-yard touchdown run with 1:39 left in the first quarter. Guerendo, a fourth-round rookie, made his first NFL start on Sunday after Christian McCaffrey and Jordan Mason suffered season-ending injuries in a loss to the Bills last Sunday night.

Midway through the second quarter, San Francisco extended its lead to 21-0 on Purdy’s 16-yard TD pass to Jennings and increased its lead to 24-0 on Jake Moody’s 23-yard field goal with 1:50 left in the first half.

“It’s a grown man’s business,” Brown said. “There is no lying down or giving up on our football team, which I really love. But we need to do a better job of trying to find ways to start games quicker, especially on the offensive side of the ball.”

“It’s not something you want to do because it puts you behind in games,” Williams said. “When you’re behind in games, which has been the case for us in some of the last few games, you have to come back and that’s a bigger task… When you come out and pounce on people and these teams and prevail. “That’s natural what you want to do at the start of a game and we haven’t done that yet.”

After the Bears cut the deficit to 24-6, the 49ers increased the lead to 31-6 on Guerendo’s 4-yard TD run on the first play of the fourth quarter.

After Odunze’s second touchdown, San Francisco extended its lead to 38-13 after running back Patrick Taylor Jr. completed a 3-yard touchdown run with 5:15 minutes left in the game.

The loss dropped the Bears to 4-9. Their next game will be against the Vikings in Minneapolis a week from Monday night.