Jeremy Maclin was taken to the locker room on a cart after his knee got tied up following a reception in the third quarter.
Chiefs coach Andy Reid said after the game that Maclin strained his knee and will have an MRI on Sunday, but NFL Media Insider later reported Maclin's injury indeed is to his ACL. Rapoport adds it's not definitive that Maclin tore his ACL and Sunday's tests will determine the severity of the injury.
Maclin exited the game with three catches for 29 yards on four targets. The Chiefs took a 20-0 lead on the drive Maclin got injured.
The loss is a huge blow for Kansas City. Maclin led the Chiefs pass attack all season, compiling 1,088 yards on 87 receptions and eight touchdown catches. Last season sans Maclin, Alex Smith threw zero touchdowns to receivers.
Maclin previously tore ACL in his right knee in 2013 (with Eagles) and 2009 (in college at Missouri).
UPDATE: Chiefs coach Andy Reid said Maclin's pain is more in his ankle-area. Reid added that Maclin will undergo further evaluation Sunday afternoon following his MRI.