San Francisco 49ers receiver Brandon Aiyuk is out for the remainder of Sunday’s game against the Chiefs due to a knee injury, NFL Network’s Tom Pelissero reported.

Aiyuk had to be taken off after conceding a gruesome-looking goal towards the end of the first half. His right knee seemed to move in a very worrying direction and he remained on the field for several moments.

Given the way his knee bent inward, Aiyuk is at high risk for an ACL or MCL injury. We’re hoping for the best, as an update on severity likely won’t come until Monday, when testing is done.

Aiyuk had two catches for 23 yards before leaving. He is one of three receivers now out for the 49ers Deebo Samuel (illness) also left the game and Juan Jennings (hip) was ruled out before kick-off.

This story will be updated.