The Gunners face a battle to bag a Europa League spot this season, but a 1-0 away win at Chelsea on Wednesday put themselves firmly back in the frame.
“But now, in the middle third and the final third, I think they've been lacking that sharpness, that real quality and intensity to go and grab a game.
“I just think they've struggled. As I mentioned, big players have not turned up.
Next season will they invest? They need to invest if they want to go to the next step and play the Arsenal way, that quick, enjoyable football to watch.
“They need changes."