Manchester United boss Louis van Gaal has warned his attacking stars: five won't go into four.

Wayne Rooney, Robin van Persie, Radamel Falcao, Angel di Maria and Juan Mata are all fit for today's clash with Southampton.

"I have said for years the highest number of players you can put in who are mostly creative is four. I still have the same opinion in 25 years. Four is a lot. So when you call these players then I have to choose," said Van Gaal.

"I always put in the best line up, not rotation. You understand the difference?

"You can call it rotation if a player is tired and then it's better to play with the other quality player, but normally I look at the qualities of my opponent, the qualities of my selection and also the mental situation of my players."