On Tuesday, the San Francisco 49ers announced via Twitter that Jimmy Garoppolo would start at quarterback against the Chicago Bears. C.J. Beathard, who has started the 49ers' last five games, was injured late in the fourth quarter during Sunday's loss the Seattle Seahawks. A hit by Seahawks defensive end Michael Bennett resulted in a knee contusion and hip strain.

Garoppolo entered with 67 seconds remaining in the game and completed both of his passes for 18 yards and a touchdown. Sunday's game in Chicago will be his third career start and first since being traded to the 49ers on October 30.

On Wednesday, head coach Kyle Shanahan met with reporters and discussed the decision to start Garoppolo over Beathard.

"Basically, it's a decision that we had to look into each week," Shanahan said. "It definitely hasn't been an easy decision. I've wanted to get a chance to see Jimmy play. I've also wanted a chance to let C.J. continue to. So, we've been trying to balance that out and also give Jimmy a chance to fully get ready.

"Like I've said throughout the whole time, the longer you wait, the more ready he'll be. I wanted to wait a while to give C.J. a chance to be ready too and had to put him in a little bit before I wanted to.

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"Same things happened a little bit with Jimmy. Like I said, he won't fully be there until next year but with everything going the way it did, also with C.J. being not able to practice today and maybe not throughout the week, made the decision a little bit easier."

Sunday's game will be a homecoming for Garoppolo. Soldier Field, where the 49ers and Bears will play, is located about 30 miles from his hometown of Arlington Heights, Illinois. He plans to have a "ton" of family and friends in attendance to watch his first start with the 49ers but isn't letting it become a distraction.

"I had to put my phone away for a little while the last couple of days," Garoppolo said on Wednesday. "I'm trying to focus. It's a great opportunity for us this week. Chicago has a very talented defense. We need to prepare throughout the week very well and get ready for those guys because it's going to be a challenge."

As Shanahan said, Beathard will not practice on Wednesday. If he can't return for the 49ers' final two practices of the week, he might not be able to suit up against Chicago. If that is the situation, the 49ers might need to look into options for a backup quarterback.

"He might not be able to suit up," Shanahan said. "I'm being optimistic, and our trainers are, and I know C.J. feels that he will be able to. He's not going to practice today. I do think there's a pretty good chance that he'll be able to get out there Thursday and Friday though. We'll see how it goes. Hopefully, he'll heal enough that he can suit up and be the backup."

The 49ers have rookie quarterback Nick Mullens on the practice squad.