In the second quarter of Thursday's loss against the Tennessee Titans, Jimmy Garoppolo suffered a thumb sprain on his throwing hand, affecting his performance in the remainder of the contest.
The injury could also affect his availability as the 49ers look to bounce back in Week 17 as they host the Houston Texans. On Monday, the team returned to the SAP Performance Facility and Garoppolo was absent from the team's first practice.
Garoppolo's absence gave third-overall pick Trey Lance first team reps during Monday's session, with the opportunity to see more playing time should the starting quarterback miss multiple practices.
Lance hasn't seen starting snaps since his first (and only) start in the 49ers Week 5 loss against the Arizona Cardinals. Per head coach Kyle Shanahan, the rookie has since made significant strides in practice which has given San Francisco confidence in Lance should Garoppolo miss time.
"I think this last month Trey has had his best consecutive four weeks of practice since we've had him. He's had a number of good days and he's had some bad days like most guys do. But as far as his consistency, I feel like this last month has been his best."
Behind Garoppolo, Lance has seen the bulk of reps as San Francisco's scout team quarterback which has enabled the 49ers to try things they normally wouldn't do with the rookie at the helm. Lauded for his speed and athleticism, Shanahan discussed the improvements in Lance's decision making over the last several weeks – something that has also been noted by San Francisco's defense.
"That just goes with how consistently - how he's throwing the ball, how he's moving, his accuracy, his decisions, everything," Shanahan said. "He gets to do a lot of stuff and try stuff you normally want to do them all the time out on scout team. And I think if you talk to the defensive coaches, defensive players or myself watching it, I think we'd all feel the same."
In his brief stints on offense, Lance has completed 25-of-48 passing attempts (52.1 percent) for 354 yards, three touchdowns and one interception. He's also rushed for 137 yards and one touchdown on 30 rushing attempts.
As San Francisco is pushing for a playoff appearance, the 49ers are likely to lean on whichever quarterback gives the team the best chance to win. And much of that will depend on health and availability.
"If your starting quarterback can't throw it as good as he normally does, that always is a factor," Shanahan said of giving Lance meaningful snaps. "I feel like if that was the case at any time this year, if Jimmy was struggling to throw it his best, I think we would've gone with Trey. So it all depends on where he is at, but I felt good to do that throughout the year."