The Early Signs That the 49ers Made the Right Choice at Left Guard

There's only room for improvement.

Oct 19, 2025; Santa Clara, California, USA; San Francisco 49ers guard Connor Colby (75) before the game against the Atlanta Falcons at Levi's Stadium. Mandatory Credit: Darren Yamashita-Imagn Images | IMAGN IMAGES via Reuters Connect

One of the biggest question marks on the San Francisco 49ers' roster this season was who was going to take the starting left guard position.

Throughout the entire offseason, no one had a clue who was going to start there. So the 49ers made it an open competition between Connor Colby, Robert Jones and rookie Carver Willis.

Ultimately, Colby won the job and we only found out just before Week 1. Across the first two weeks against the Los Angeles Rams and the Miami Dolphins, Colby has performed solidly enough to show that they may have made the right choice.

He has faced 61 pass-blocking opportunities, allowing just two pressures and no sacks, while recording a 98.4 pass-blocking efficiency and zero penalties.

Pro Football Focus gave him an overall 72.6 pass-blocking grade, ranked 14th out of 62, and his 61.8 run-blocking grade ranked 26th, showing a player who has been more effective at protecting Brock Purdy than opening running lanes.

It's an area that has seen Purdy excel. He was their leading rusher in Week 2 against the Dolphins, as he went 20 for 22 in one of his best performances he's had in red and gold.

Oct 19, 2025; Santa Clara, California, USA; San Francisco 49ers guard Connor Colby (75) before the game against the Atlanta Falcons at Levi's Stadium. Mandatory Credit: Darren Yamashita-Imagn Images | IMAGN IMAGES via Reuters Connect

It's an encouraging start for Colby, but there's plenty of room for improvement. His 61.8 run-blocking grade is respectable, but it leaves room for growth. If he can become more consistent at creating movement at the line of scrimmage while maintaining his current level of pass protection, he should be able to help Christian McCaffrey and Kaelon Black maintain explosiveness.

He didn't have a great game against the Rams in Week 1, but it showed that he has to step up against the tougher opposition in this league. San Francisco has some tough opponents on this year's schedule, namely the Seattle Seahawks (twice), a non-jet-lagged Rams team, the Kansas City Chiefs and the Philadelphia Eagles.

Bear in mind, this is only Colby’s sophomore year in the league. He is still young and developing, meaning there is plenty of room for growth as he gains more experience.

That makes his early performances even more encouraging. Colby has already shown that he can provide reliable pass protection, while his run blocking remains an area where he can continue to develop.

Ultimately, the 49ers’ decision to thrust Colby into the starting role will be judged in the tougher fixtures, but it seems he's performing at a decent level.

But any Shanahan offensive line needs to be great, not just decent. You know, play to Purdy's strengths.