Millwall could be missing top-scorer Lee Gregory this weekend when they take on Brighton and Hove Albion in the FA Cup quarter-final.

The Lions’ striker was taken off midway through the second half in the win over Birmingham City last night with a calf injury.

Gregory was leading the line alone when the ball went out on the far side for a throw-in where the striker went down after challenging for a header.

He was subsequently replaced by Steve Morison.

Neil Harris confirmed after the game the Millwall striker was withdrawn with a tight calf.

“Lee Gregory came off with a tight calf.

"[It is] too early to tell for Sunday. We will have to see how he goes towards the weekend,” he told Football.London.

If the striker misses out this Sunday that could mean a recall for any number of attacking options with Morison, Tom Elliott and Aiden O’Brien all vying for a starting place.

As Harris said, however, it is too early to tell, and Gregory will be assessed as the week progresses to determine his fitness ahead of the cup-tie and international break that follows it.

The verdict

This could be a massive blow to Millwall’s cup chances, and could even damage their survival bid.

It depends on how severe the problem is.

Gregory’s ailment could clear up in a day, a week, or three weeks – it remains to be seen until the injury has been fully assessed.

Millwall fans will be worried about their main man up top and their chances of progressing to a Wembley semi-final ahead of an international break before a trip to Leeds United.

Worrying times at present.