SHAUN Hutchinson is set to be out of action until at least the middle of October with a knee injury.
Centre-back Hutchinson suffered the setback against Sheffield Wednesday last week.
Byron Webster and Murray Wallace are in competition to partner Jake Cooper in the centre of Millwall's defence against Swansea on Saturday. Wallace started his first league game against Rotherham last Sunday.
Lions boss Neil Harris said: "I'm trying to be as honest as I can with it in the sense of saying that we're probably looking at about a six-week period. That's a rough estimate at the moment, it's still early days.
"It's a real freak one. He got a challenge around the 45-minute mark and played the rest of the game with no problems.
"He was fine getting on the bus, but got off the bus and he was in a really bad way. He came in the following day and his knee had swollen up.
"It's a crazy one and it's unfortunate for him and us. He's a really big part of our squad, vice-captain to the team.
"We try to limit injuries to the bare minimum with a tight squad, but this is a freak one that we can't avoid, same as we had with Byron Webster and Shaun Williams last year.
"But Murray came in and did well on Sunday and Byron is edging towards full fitness all the time. With Byron it's just about getting that little bit of sharpness. He's come on really well."
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