SANTA CLARA — The 49ers likely will be without Brandon Aiyuk for the rest of the season, as the wide receiver is feared to have sustained an ACL injury in Sunday's 28-18 loss to the Kansas City Chiefs at Levi's Stadium.
“We are worried it’s an ACL,” 49ers coach Kyle Shanahan said after the game. "Not confirmed yet, but we will find out for sure tomorrow.”
Aiyuk’s injury, suffered late in the first half, is a huge blow to the 49ers' receiver group, which was considered the deepest position on the roster.
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But it isn't time for the 49ers to look outside the building for help -- at least not yet. Shanahan now needs his own players -- if they can quickly recover from illness and injury -- to step up.
In the past, Shanahan has leaned on Deebo Samuel to carry the load, but on Sunday morning, the wide receiver was struck with an illness that he initially tried to play through.
Samuel was on the field for early warmups, but he did not return for pre-game drills. The All-Pro eventually came back and tried to play, but he couldn't catch his breath, leaving the field a few minutes before halftime and not returning.
In the week leading up to the game, Samuel dealt with a wrist injury that limited him in practice, but by Friday, he was not on the 49ers' injury report. He most likely will be able to play next Sunday night against the Dallas Cowboys.
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The 49ers already were without Jauan Jennings, who's still working through a hip injury he suffered in a Week 6 win in Seattle. Shanahan does not believe Jennings' injury is considered long term, and he hopes to have the third-down specialist back next week.
Without the 49ers' top three wide receivers on the field, rookies Ricky Pearsall and Jacob Cowing saw extended second-half playing time alongside second-year pro Ronnie Bell and veteran Chris Conley.
The first-round draft pick’s return couldn’t have happened at a more opportune time. After Pearsall played just 17 offensive snaps in the first half, he took a more prominent role in the second half, on the field for nearly every play.
While the rookie's stat line was modest -- he caught three of his five targets for 21 yards -- Shanahan likely will integrate Pearsall into the offense even more, if Aiyuk indeed misses the remainder of the season. The Florida product is a savvy route runner and could shoulder more responsibility.
The offense also could turn to Cowing, who has undeniable speed and can stretch the field. The rookie caught two of his three targets for 50 yards Sunday -- with one catch on a deep go-route for 41 yards.
While the 49ers lost one of their biggest playmakers in Aiyuk, there still have capable receivers. But if they suffer another significant injury, they might need need to look elsewhere before the Nov. 5 NFL trade deadline.