Abou Diaby says that new striker Marouane Chamakh has been a key signing for Arsenal this season.

The former Bordeaux man has been outstanding so far this term.

Diaby said: "They (new signings) bring us a lot, especially Marouane, who has a different profile to Robin Van Persie's. He's great with his head and that's a real bonus, because a lot of our play goes down the flanks with many crosses.

"Marouane has a good instinct inside the area, he is able to get ahead of the defender and get his head in there. He does this role marvelously well, he's the striker we needed."