The 49ers put Tennessee away, then let the Titans back in for a 37-24 win that featured efficient offense and concerning defense. Brock Purdy and Ricky Pearsall

Brock Purdy receives honest words from a teammate after leading the San Francisco 49ers to a 37-24 victory over the Tennessee Titans.

San Francisco 49ers wide receiver Ricky Pearsall is dealing with an injury in the first quarter of the Week 15 game against the Tennessee Titans.

The San Francisco 49ers were expected to beat the Tennessee Titans, and they were expected to do it by about two scores.

The San Francisco 49ers are set to part ways with WR Brandon Aiyuk, and head coach Kyle Shanahan didn't mince words when explaining the decision.

The Niners officially placed Aiyuk on the NFL’s reserve list on Saturday, with a “left squad” designation. It’s an incredibly rare roster move —- so much so that OverTheCap, a website all about tracking the minutiae of NFL salary machinations, doesn’t even keep track of it. “Left squad” usually indicates a player quit on the team.

San Francisco 49ers coach Kyle Shanahan called the decision to put missing receiver Brandon Aiyuk on a season-ending reserve list an easy one and it won’t change what the team plans to do the rest of the season.

Ricky Pearsall receives a strong message following the San Francisco 49ers’ win over the Tennessee Titans in Week 15.

The Tennessee Titans couldn't keep up with the methodical, forward-moving offense of the San Francisco 49ers, dropping the Titans in the loss column.

As the 49ers prepare for Sunday’s matchup against the Tennessee Titans, McCaffrey’s availability has become a storyline. Earlier in the week, he battled an illness that limited his practice time, though he was able to log a full session on Friday.