San Francisco 49ers offensive linemen Ben Bartch (78), Dominick Puni (77), Trent Williams (71) and Colton McKivitz (68) during an OTA at Levi's Stadium. Mandatory Credit: D. Ross Cameron-Imagn Images D. Ross Cameron-Imagn Images

49ers place starting offensive lineman on injured reserve

Originally posted on San Francisco 49ers on SI
By Grant Cohn | Last updated Sep 17, 2025 2:57 PM ET

The 49ers offensive line just took a hit.

Starting left guard Ben Bartch, who suffered a high-ankle sprain on the sixth play of the 49ers' 26-21 win over the Saints on Sunday, has been placed on Injured Reserve. That doesn't mean his season necessarily is over, but it does mean he has to miss at least the next four games. But even if/when he returns, the 49ers can't count on him to stay healthy for more than a couple games at a time.

Why the 49ers never should have counted on Bartch

Last season, Bartch was the 49ers' backup left guard behind Aaron Banks, who's a decent starting offensive lineman. Those aren't easy to find in the NFL, which is why the Packers signed Banks for $19 million per season this year.

The 49ers didn't want to pay Banks all that money, so they Bartch to a cheap one-year extension. Bartch is a former fourth-round pick who shows promise when healthy, but he's rarely healthy. In 2024, Bartch started two games when Banks was injured, and in Bartch's second start, he suffered a season-ending injury. The 49ers thought he showed enough in those two starts to warrant an extension. Now, he's injured again.

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Bartch's replacement at left guard is rookie Connor Colby, who was a seventh-round pick. In fairness to Colby, he held his own after replacing Bartch on Sunday. Still, Colby has a ton to prove the rest of the season. And if he goes down, the next man up will be undrafted rookie Drew Moss. Which means the 49ers are extremely thin on their offensive line.

You'd think the 49ers would have signed someone better than Bartch to replace Banks, considering they also gave their quarterback, Brock Purdy, $53 million per season this offseason, and protecting the highest-paid player on the team is pretty important. Instead, they invested as little as possible in the interior of their offensive line, and now Purdy is injured already after scrambling away from pressure in the pocket during Week 1.

If Colby stays healthy and plays well, the 49ers most likely will keep him in the starting lineup because Bartch is completely unreliable, and continuity is important for the offensive line. Still, you wonder if the 49ers privately are kicking themselves for not drafting an offensive lineman earlier than Round 7 this year, considering it has been one of the weakest positions on the team for a decade.

This article first appeared on San Francisco 49ers on SI and was syndicated with permission.

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