Sheffield United boss Chris Wilder is furious with a dressing room mole.

Wilder's team news has been leaked regularly before matchday kickoff this season.

Everybody will know the team (for Boxing Day) anyway because it will come out on Twitter at about half ten in the morning," said Wilder for their Boxing Day clash with Luton.

"I will comment on it. It's quite difficult to keep the team quiet but I'm not happy about that situation.

"Whoever did it, I appreciate that. Thanks very much. I'm going to have to tighten everything up around the training ground. It's a lesson learnt for me as well.

"That person who did it. Call yourself a Sheffield United fan? I don't think they are. It's an absolute joke."