One area in which the backup-heavy 49ers struggled early in the season was the run game. McCaffrey averaged fewer than three yards per carry through the first few weeks and couldn’t break any big gains. The offense had to lean on him as a pass catcher, not as a runner.

Trent Williams, Darnell Washington and Geno Smith were among the NFL players injured in Week 17. Injured players will be evaluated this week.

Left tackle Austen Pleasants filled in admirably for Trent Williams and may need to do it against Seattle as well.

Trent Williams is one of the best linemen in modern NFL history, and the Sooner great suffered an injury on Sunday Night Football.

But it’s not all good news for the 49ers. Left tackle Trent Williams was shaken up on the first play from scrimmage — Purdy’s pick-six — and is questionable to return with a hamstring injury. Austen Pleasants came in to replace him.