That changed this week when the 49ers placed starting left guard Ben Bartch on injured reserve following a high-ankle sprain suffered against the New Orleans Saints. With Bartch sidelined, Colby is preparing for his first NFL start—and if he impresses, he could hold onto the job long-term.
According to Pro Football Focus (PFF), Colby has earned a 73.6 pass-blocking grade on 39 pass-blocking snaps this season. Bartch, in comparison, posted a 61.7 pass-blocking grade on 49 snaps but graded higher as a run blocker, with a 76.4 mark compared to Colby's 55.4. The numbers highlight Colby's upside in pass protection while leaving room for growth in the run game.
General manager John Lynch joined Bay Area radio station KNBR on Thursday, praising the rookie's ability to step in seamlessly. He admitted that you can't always predict how a draft pick will immediately perform. The team liked what they saw from Colby in his college film, acknowledging that Iowa's blocking scheme has similarities to the 49ers', particularly when it comes to run-blocking.
"The coolest thing I can say about Connor is he stepped right in," Lynch said. "That was a good defensive front that we played against in New Orleans, and he handled it well. He played consistently. He played well in the pass game—he pass blocked extremely well. He was good in the run game. It certainly wasn't too big for him.
"The question now is, can he continue to do that and do it consistently week in, week out? He's going to have that opportunity. We put Bartch to IR. He had a high-ankle sprain. Ben was playing well, and so that was unfortunate. But, this league, that's what it's all about—being prepared such that when your opportunity comes, you can go perform at a high level, and Colby certainly did that."
Head coach Kyle Shanahan admitted that he wasn't shocked by Colby's ability to step into the offensive lineup and perform at a high level, and expects that to continue on Sunday against the Arizona Cardinals.
"I think pass [protection] has kind of been his strength we've noticed since he's been here," Shanahan said. "He has been a tough guy to get around. We could see it in one-on-ones early in camp. I think his adjustment has been a little bit more of the run game, just a little bit more our style. I think it was in that game, too, versus New Orleans.
"But no, that's why he made our team. He beat out some good players, some guys who have been in this league before. So, I think in order to do that, we've got to feel pretty high on him."
Through 62 offensive snaps, Colby has yet to allow a single pressure. As the 49ers prepare for Sunday's NFC West matchup against the Arizona Cardinals, all eyes will be on the late-round rookie who suddenly finds himself with a golden opportunity to secure a starting role.
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