Manchester United boss Sir Alex Ferguson admits some players will be leaving the club this summer.

Ferguson feels changes in personnel are inevitable.

"You have to take a decision about where we can improve the team," Ferguson told MUTV.

"When you are challenging for four trophies it can have a draining effect. You have to be aware of that and spot the moment when it is time to freshen up one or two players.

"It is not a desire to do it but you need to do it because the demands and pressures on players can, over time, be quite exacting."