49ers’ Brandon Aiyuk (knee), Deebo Samuel (illness) ruled out for second half vs. Chiefs

SANTA CLARA — The 49ers’ already depleted offense has taken two more hits.

San Francisco announced that wide receivers Brandon Aiyuk (knee) and Deebo Samuel (illness) have been ruled out for the second half against the Chiefs at Levi’s Stadium, leaving the 49ers without their top-three receiving options.

Samuel, who the 49ers announced as having an illness prior to kickoff, was initially listed as questionable to begin the second half, but was then downgraded to out following the 49ers’ first drive of the third quarter.

San Francisco entered the day already without Jauan Jennings, who has a team-high 404 receiving yards. Aiyuk (374) and Samuel (335) rank second and third, respectively, in receiving yards for the red and gold. Running back Christian McCaffrey, last season’s leading rusher, hasn’t made his season debut due to Achilles tendinitis.

With less than a minute remaining in the second quarter, Aiyuk’s right leg bent awkwardly after being tackled by the Chiefs’ Chamarri Conner and Trent McDuffie on a 15-yard reception. Aiyuk remained on the grass for several minutes before walking off the field and straight to the blue tent under his own power.

Samuel, who finished the day with no catches and no targets, was seen wearing an oxygen mask in the middle of the first quarter. Samuel did not play in the second quarter and headed to the locker room prior to the end of the first half.

In place of Aiyuk and Samuel, the 49ers called upon rookie wide receivers Ricky Pearsall, making his NFL debut after being shot on Aug. 31, and Jacob Cowing. Pearsall received a standing ovation after hauling in his first career reception, a six-yard grab in the second quarter. Cowing, drafted in the fourth round out of Arizona, entered play without a reception or receiving yard as a professional.

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