49ers fear Brandon Aiyuk suffering season-ending ACL tear in loss to Chiefs

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

Shanahan says the 49ers fear Aiyuk has a torn ACL, which would sideline him for the remainder of the season. 

"That’s what it looks like, but we don’t know for sure," Shanahan said, per 49erswebzone.com. "Just doing the test and everything with our hands, and with the trainers and stuff, all that. That’s what we fear. That’s what it looks like, but we’ve been wrong before, so we’re praying that we are."

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Aiyuk will undergo further testing to confirm the 49ers’ fear. 

Aiyuk caught a pass from quarterback Brock Purdy with 37 seconds left in the half, and he took it for 15 yards with Justin Reid and Chamarri Conner tackling him simultaneously. 

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However, as Reid was trying to bring him down, Conner came sprinting in and threw his body at Aiyuk’s leg. Video replay of the tackle showed Aiyuk’s right knee buckle, and he was in immediate pain down on the field. 

Aiyuk needed to be carted off the field after trainers assessed what he was going through. 

The injury came after the 49ers were already without Deebo Samuel, who tried to play through an illness but ultimately had to bow out early in the 28-18 loss to Kansas City. 

It also comes after an absolute rollercoaster for the talented receiver this offseason, when he was seeking a new long-term extension instead of just playing on his fifth-year option. 

The 49ers and Aiyuk went back and forth, as the latter requested a trade and the former eventually told him just before the season he would be forced to practice. Both sides ultimately agreed on a four-year, $120 million deal that locked Aiyuk back in with the Niners long-term. 

Through six games, Aiyuk has totaled 351 yards through the air on 23 catches (41 targets), but he did not find the end zone once this season. If this is an ACL tear, Aiyuk will end the year with those numbers as the 49ers set him up on a recovery path with 2025 in mind. 

The 49ers’ offense is a group filled with talent, but Aiyuk is the latest serious injury to Shanahan’s group. Christian McCaffrey is the obvious piece missing at the moment, as he is dealing with Achilles tendinitis in both feet. 

San Francisco was expected to be a Super Bowl contending team again this season, but it has not been a dream start for them as they dropped to 3-4 with the loss to the Chiefs now.  

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