The Kansas City Chiefs lost starting right tackle Mitchell Schwartz to a back injury in the first half of Monday night's 26-17 win over the Buffalo Bills.
Schwartz, 31, started the game after being listed as questionable to play on the final injury report of the week.
Starting left guard Mike Remmers moved to right tackle after Schwartz left the lineup. Remmers was replaced by Nick Allegretti.
Until last season, Schwartz hadn't missed a snap since arriving in the NFL in 2012 with the Cleveland Browns. He left the Chiefs' lineup last year for a handful of snaps during a game against the Tennessee Titans.
The Chiefs also lost backup defensive end Alex Okafor during the Bills game with a hamstring injury.