Olympique Marseille coach Didier Deschamps admits stopping Robin van Persie is key to beating Arsenal.
The Dutchman is in contention to face Marseille once more after featuring at the Stade Velodrome two weeks ago and Deschamps knows his players must be at their best to stop the in-form striker.
"If he is not the best forward in Europe he is certainly one of the best," he said. "What you ask from a striker is to score goals and his strike average is really impressive.
"Maybe he has a team that plays a lot for him. There are some players that when in front of goal would rather pass - Gervinho or Walcott for example would sometimes do this.
"But he is one of the top players in Europe at the moment, of course.
"To block him would be the ideal thing to do. But ideally we should be looking to stop him from getting too many balls so he doesn't have too many opportunities."