The San Francisco 49ers have endured a hugely disappointing season, and it was encapsulated by Christian McCaffrey's first half in their Week 13 game with the Buffalo Bills.

McCaffrey was enjoying his best game since returning from bilateral Achilles tendinitis last month, finding plenty of room to run and displaying the explosiveness that was clearly lacking in recent weeks.

But his promising start game to a grinding halt after an 18-yard rush in the second quarter.

Two plays later, an evidently struggling for McCaffrey slid down for a five-yard loss and headed straight to the blue medical tent on the 49ers' sideline before being declared questionable to return with a knee injury.

Here’s the play on which Christian McCaffrey injured his knee: pic.twitter.com/r4X28vx6rV

— Adam Schefter (@AdamSchefter) December 2, 2024

McCaffrey had 67 yards from scrimmage at the time of leaving, having managed just 68 in the entire game against the Green Bay Packers last week.

Though the 49ers were trailing 7-3 at the time of McCaffrey's exit, him being back to his best would have been a reason for San Francisco to retain hope of an upset to get back to 6-6.

Instead, after a Jake Moody missed field goal, the 49ers immediately gave up a 65-yard rushing touchdown to James Cook, leaving them in a 14-3 hole with the reigning Offensive Player of the Year once again nursing an injury.

There have been a lot of problems that have contributed to the Niners' struggles this year, but the misfortune McCaffrey suffered against the Bills was their season in a nutshell, and it will likely leave them trying to thread an incredibly thin needle to even make the playoffs.

Brock Purdy’s game status for Week 13 clash with Bills confirmed as 49ers make surprise QB move

An unexpected decision.