SANTA CLARA, Calif. — Chris Foerster says there’s a level of performance — a line — an offensive lineman must stay above for his team to be successful.

“If you can play above that line, it doesn’t matter if you’re one inch above the line or if you’re Trent Williams and you’re 100 miles above the line,” the San Francisco 49ers offensive line coach said Thursday. “As long as you’re above the line, you can play winning football.”

So where on that scale did newcomer Austen Pleasants land last Sunday?

“He was hovering just above the line,” said Foerster, who was conspicuously stingy in his praise of Pleasants despite the offensive lineman’s humble NFL background, his sudden shove into the limelight on Sunday and the 49ers’ gaudy offensive output in the win over the Chicago Bears. San Francisco set season highs in points and yards, and its longest run of the season — Christian McCaffrey’s 41-yarder in the first quarter — came off of left tackle, where Pleasants was lined up.

“It wasn’t quite what we wanted, but it was good enough,” Foerster said of the performance.

Why such a tepid review? It’s likely because Pleasants, 28, might have to perform under even more pressure against a much better opponent on Saturday. Williams, the team’s perennial Pro Bowl left tackle, missed every practice this week after straining his hamstring on the first snap Sunday and is questionable to play against the Seattle Seahawks.

Kyle Shanahan said Williams made “good progress” during the week and that the 49ers will weigh the importance of winning Saturday, which would give them a first-round bye and home games throughout the playoffs, against Williams aggravating the injury. Lose to the Seahawks, and the 49ers will have to play on the road next week.

“I definitely don’t want to lose any players for the following week knowing we’re in the playoffs, but I also look at when you’re playing to play one less playoff game, you can look at that as a playoff game,” Shanahan said. “I know the season’s not over if we lose, but you’ve still got to go play a game the next week on the road if you lose. And you can completely avoid that by winning. So I see this as a playoff game, too.”

If Williams doesn’t play, Pleasants would make the first start of his career.

Since entering the NFL as an undrafted rookie in 2020, he’s bounced among seven teams’ practice squads, picking up only a smattering of regular-season offensive snaps along the way.

He had a remarkably bland career when the 49ers brought him in for a tryout in December of 2024. Foerster couldn’t even remember the audition, and there was nothing to indicate then that Pleasants was capable of starting in a game with playoff-like pressure.

“The thing is, at that time of year, usually everybody (with talent) is gone,” Foerster said. “There’s no pool to choose from — the quality players are on teams, they’re on practice squads or they’re injured. It’s very slim pickings.”