Santa Clara, Calif. — When Jimmy Garoppolo made the first two starts of his career, he knew the role was temporary with Tom Brady waiting to return from suspension in New England.

It's a far different case as Garoppolo prepares to make his first start for San Francisco (1-10) on Sunday in Chicago. The 49ers traded a 2018 second-round pick to the Patriots to acquire Garoppolo last month with designs of him becoming the franchise quarterback in San Francisco.

"I'm trying not to think about the future too much," Garoppolo said Wednesday. "I've learned in the past that when your mind wanders like that, quarterbacking in this league is hard enough. So, when you start thinking about other things you're going to have a tough time. I think just staying focused on the Bears this week. I hold myself to a high level. I've been doing that my whole life and I think that won't stop."

Coach Kyle Shanahan would only commit to Garoppolo starting this week, saying he will evaluate the quarterback position on a weekly basis. Shanahan has been clear about how highly he thinks of Garoppolo as evidenced by the trade and the willingness to use the franchise tag this offseason to keep Garoppolo if needed at a contract that would be worth close to $25 million for one season.

The decision to make the move this week was made in part because C.J. Beathard injured his knee and hip last week and was unable to practice Wednesday. Shanahan said he did not know whether Beathard would be healthy enough to serve as the backup this week, but Beathard said he didn't think it would be an issue.

Either way, Shanahan is excited to see Garoppolo in game action instead of performing in scripted practices to get a better sense of what he's capable of doing heading into next season, when Garoppolo is expected to be the starter.

"Whether it comes off as a negative or a positive, you hope in the long run it's all positive because you hope he learns from the reps that he gets, and hopefully we can help him have some success. And when he doesn't, I hope it ends up making him better throughout each week he does get to play," Shanahan said. "I hope that leads to him being better next year and understanding going into the offseason a little bit of what it felt like."

While Garoppolo has been with the team for four weeks — about the time of training camp — Shanahan said it's not nearly the same as the work that gets done in the summer. Garoppolo has gotten only a handful of time with the starters in practice, when he spends much of his team running the opposing offense as part of the scout team.

He got the opportunity to come in and play for a few plays last week after Beathard left with the injury late in a 24-13 loss to Seattle. Garoppolo completed both passes, including a 10-yard touchdown to Louis Murphy that showed his ability to fit passes into tight windows because of his strong arm.

"Jimmy has the ability with his quick release that he doesn't always have to anticipate," Shanahan said. "He can make up for it if he's a hair late. He has the speed and quick twitch in his body to get it there and overcome some things."

Garoppolo has little NFL game film to go on, but his performance in those two starts last year when Brady was suspended was impressive and made him a highly sought quarterback. He completed 42 of 59 passes for 496 yards, four touchdowns and no interceptions in wins against Arizona and Miami.

He got hurt in the second quarter of his second start and has thrown just six passes since, including the two on Sunday. But he gets a big chance on Sunday.