Former Manchester United manager Sir Alex Ferguson has heaped praise on Arsene Wenger following the Frenchman's announcement that he will leave the club at the end of the season.

Wenger is the only manager to have taken charge of more Premier League games than Ferguson, and the rivalry between the two clubs while both managers were at their peak is arguably the defining one of the Premier League era.

The long-time adversaries often clashed during a number of memorable meetings, but Ferguson insists that he always had respect for Wenger and admits that he learned from the Arsenal manager's approach to the sport.

"When Arsene came to Arsenal, he changed a lot of the eating habits and fitness regimes at the club. He was ahead of the game at that particular time. We took examples, as we always tried to take examples from anybody who was improving," Ferguson wrote in the United programme prior to this afternoon's Premier League clash between the two sides.

"It was like when you're driving along the road: you have to be aware of somebody coming up in your wing mirror, trying to overtake you. That was the case with us and Arsenal for quite a few years.

"Virtually every game we played against Arsenal, there was a real edge to the match. There were confrontations, because there were two teams and two managers battling for one award: the Premier League. In my time, we had a few arguments but I always did really respect the man because he did a fantastic job at his club."

Arsenal go into today's game knowing that anything other than a win would end their top-four hopes once and for all.