Injuries have forced Thomas to play. The team lost starter Jason Verrett to a torn ACL in Week 1. Emmanuel Moseley was placed on injured reserve due to a high-ankle sprain earlier this month.
Thomas has played 181 defensive snaps over the past three games compared to the 20 he played in the games before that. Thomas was even inactive for five of the 49ers' first seven games.
General manager John Lynch joined KNBR on Thursday and shared that he believes San Francisco has a future starting cornerback in Thomas. However, there are still some things to overcome before that happens.
"I really feel convicted that we've got a starting corner for years to come," Lynch said. "And that's what we thought when we drafted him. We also knew that there was some inherent physical development that needed to take place, and I think that still remains. And we're not going to fix that this year. He's just got to kind of grow into his body a little bit.
"I told Ambry after that game against Cincinnati, 'Man, you're doing the hard part. You're putting yourself in position.' And now, it becomes a mentality. I probably used a bad example because I was talking Dennis Rodman with him, and he probably didn't know who Dennis Rodman was. It's a mentality [he needs to have]. 'When that ball's up there, that's my ball.'"
Last week against the Tennessee Titans, Thomas earned his highest Pro Football Focus grade after what the analytics site saw as two poor outings against the Bengals and Atlanta Falcons. His coverage grade of 65.2 in Week 16 was his highest of the season.
"So I think, as he continues to grow, he's got a really good feel for playing the position," Lynch continued. "I think he's answered some of the physicality things that showed themselves early in training camp, and I think he's really coming along. In a nice way, he's kind of been force-fed here, but he's answered the call.
"I think it will get better each and every week, and we need it to because [of the injuries] going back to the first game of the year, when Verrett went down, and then Emmanuel Moseley struggled to stay healthy this year. So he's been called upon, and I'm proud of the kid the way he's answering the call."
You can listen to the entire conversation with Lynch below.
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