Both teams' offenses struggled to find a rhythm early in the first half, but the Bears managed to hit their stride before the second quarter came to a close, engineering an eight-play, 75-yard drive that ended with a four-yard touchdown pass from Trubisky to receiver Anthony Miller.

"It's just a little spring out timing route and [Miller's] selling the fade and then he comes back and stops on a dime," Trubisky said of the play. "He ran a heck of a route, and I just put it in a spot where I felt like he could catch it."

It was the only touchdown pass for either side on the day.

Trubisky finished the day connecting on 25 of 29 passes for 246 yards. His completion percentage of 86.2 is the highest single-game completion percentage for a Bears quarterback since at least 1960.

Trubisky credits his success to trying to simplify things and allow his receivers to make the plays.

"Especially at the end you're thinking playmakers not plays," Trubisky said.

Of Trubisky's 25 completions, 20 went for 10 yards or fewer, a testament to his less-is-more approach.

The only play that got Trubisky in trouble was a second quarter attempt in which he missed Miller and was picked off. Luckily for the Bears, the 49ers were flagged for a holding penalty on the play, negating the interception.

"I was just scrambling around, doing too much," Trubisky said. "I probably could've just ran and got out of bounds looking back on it. The ball just didn't come out the right way I wanted it to."

Trubisky didn't let the miscue get to him and connected with Miller three plays later for the score.

"He was out there working like he's supposed to," Miller said of Trubisky. "That's what we expect out of Mitch every time. We think he's an elite quarterback and he can take us all the way."

In the second half Trubisky was nearly perfect, completing 16 of 17 passes. His 94.1 completion percentage in the second half is the highest second-half rate by a quarterback in the league this season. Trubisky also etched his name into the Bears' record book in the second half by becoming just the sixth quarterback in team history to throw for more than 3,000 yards in a season. Trubisky has 3,060 passing yards with one game remaining.

Nagy said the accuracy is the biggest sign of growth from the young quarterback.