Manchester United legend Roy Keane worries the pressure of playing for the club takes its toll on players.

Keane was asked about the reasons for United struggling so much since Sir Alex Ferguson's retirement.

Despite mega millions spent on transfer fees and several high profile managers hired over the years, United have no Premier League titles since Sir Alex left.

"We don't know the characters or what the feel of this dressing room is," Keane said in the build-up to United's 2-2 draw against Tottenham in the Premier League on Sunday.

"We look around, we've got players here who have won big trophies. They've won World Cups.

"I don't know what the dynamics are like in the dressing room, but you just hope that when they have come to United that they've enjoyed the pressure of playing for Man United. We've been critical of United the last few years, recruitment, the facilities. But we've come here early this morning. It's still a great place to come and play football. It really is.

"I just hope there are enough characters and leadership to get United back to winning ways. It's a long way back. Sometimes there are players that come to Man United, as we've seen, and it looks like the pressure of playing for Man United has been a bit too much for them."