Leeds United were handed an early injury blow against Luton Town when skipper Liam Cooper was forced off just six minutes into the first-half.
Marcelo Bielsa's men are hosting the Hatters looking to extend their lead at the top of the Championship table following their emphatic 3-0 win over Fulham on Saturday, but suffered an early setback when Cooper went down injured.
The Whites skipper went down after leaping to clear a Callum McManaman free-kick in a busy penalty area with just six minutes on the clock.
After undergoing treatment, he made his way to the sideline in clear discomfort holding his lower back and left hip.
The 28-year-old was unable to continue and was replaced by Gaetano Berardi, who signed a short-term extension at Leeds earlier this month.
This is the first of seven games in 22 days for Leeds and losing their captain for any extended period of time will come as a blow to their title hopes.
Bielsa will give an update over his skipper's fitness in his post-match press conference.
