Arsenal legend Martin Keown has explained why he would "lose his rag" with former Manchester United ace Ruud Van Nistelrooy.

Keown says Fulham's defenders must not fall into the trap of doing the same when facing the Hamburg striker in tonight's Europa League clash.

The former England international wrote in his Daily Mail column: " Ruud van Nistelrooy was up there with the best strikers I played against but you couldn't trust him - which is why I ended up losing my rag with him.

"The fundamental thing about him is that he was always looking to test referees. He was strong and physical when he wanted to be but when he was in and around the box, he went down like a pack of cards. You would go into a strong challenge one minute and he would bounce off it. The next, he would be rolling around on the ground.

"Every challenge brought a different reaction so you started to think twice about making them when you were near the box. That was annoying and if you compared him to someone like Mark Hughes, who was quite consistent in the way he played, he was difficult because he just fell over when it suited him. It used to infuriate me."