San Francisco 49ers head coach Kyle Shanahan expressed what the organization thinks star receiver Brandon Aiyuk might have after he was carted off the field against the Kansas City Chiefs on Sunday.

Shanahan says the 49ers fear Aiyuk has a torn ACL that would sideline him for the rest of the season.

“It looks like that, but we don’t know for sure,” Shanahan said, according to 49erswebzone.com. “We just do the test and everything with our hands and with the trainers and stuff. This is what we fear. That’s what it looks like, but we’ve been wrong before, so we pray.”

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San Francisco 49ers wide receiver Brandon Aiyuk, #11, catches a pass between Kansas City Chiefs cornerback Trent McDuffie, #22, and safety Chamarri Conner, #27, during the second quarter at Levi's Stadium. (Cary Edmondson-Imagn Images)

Aiyuk will undergo further testing to confirm the 49ers' fears.

Aiyuk caught a pass from quarterback Brock Purdy with 37 seconds left in the half and took it for 15 yards while Justin Reid and Chamarri Conner tackled him at the same time.

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However, as Reid tried to take him down, Conner sprinted in and threw his body onto Aiyuk's leg. A video recording of the tackle showed that Aiyuk's right knee buckled and he immediately felt pain on the field.

Aiyuk had to be carried off the field after trainers assessed what he was going through.

The injury came after the 49ers were already without Deebo Samuel, who attempted to play due to an illness but was forced out early in the 28-18 loss to Kansas City.

San Francisco 49ers wide receiver Brandon Aiyuk, #11, struggles on the ground after suffering an injury in the second quarter against the Kansas City Chiefs at Levi's Stadium. (Cary Edmondson-Imagn Images)

It also comes after an absolute rollercoaster ride for the talented receiver this offseason, as he sought a new long-term extension rather than just playing up his fifth-year option.

The 49ers and Aiyuk went back and forth, as the latter requested a trade and the former finally informed him shortly before the season that he would be forced to practice. Both sides ultimately agreed on a four-year, $120 million contract that ties Aiyuk back to the Niners in the long term.

In six games, Aiyuk has totaled 351 yards through the air on 23 catches (41 targets), but he hasn't reached the end zone once this season. If it's a torn ACL, Aiyuk will finish the year with these numbers as the 49ers have put him on a recovery path heading into 2025.

The 49ers' offense is loaded with talent, but Aiyuk is the latest major injury to join Shanahan's group. Christian McCaffrey is obviously out at the moment as he is suffering from Achilles tendonitis in both feet.

San Francisco 49ers wide receiver Brandon Aiyuk, #11, walks onto the field before the start of the game against the Kansas City Chiefs at Levi's Stadium. (Cary Edmondson-Imagn Images)

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San Francisco was expected to be a Super Bowl contender again this season, but it hasn't been a dream start for them as their loss to the Chiefs has now dropped them to 3-4.

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