Ian Holloway has said that watching his Millwall team "capitulate" in Wednesday's 4-0 FA Cup defeat to Bradford City was among the low points of his managerial career.
Mark Beevers was sent off after just six minutes as goals from James Hanson, Jon Stead and Andy Halliday helped the League One side into a 3-0 half-time lead in the third-round replay.
Billy Knott added a fourth midway through the second half, and Holloway has moved to apologise to fans who made the 200-mile trip to Valley Parade.
"The lack of confidence in the team and in each other, we let a goal in almost straight away," he told Sky Sports News.
"You could see how bad it is for everybody and in all my time in football I've never seen a team capitulate as bad as that.
"All I can do is apologise to the fans. We've got so much work to do. The lads don't look like a Millwall team, they didn't have any fight in them, they don't look like my team."
The Lions sit 22nd in the Championship table, two points adrift of safety.
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