Mikel Arteta admits he was hurt when Robin van Persie quit Arsenal for Manchester United last summer.

The Spanish midfielder concedes the move did hit team morale.

"I was very disappointed when Robin van Persie left us last year. He was the man who made the difference.

"I didn't want him to go but we had to accept that he wanted to move on to a new challenge at Manchester United.

"There's a difference in spirit when you are trying to sell players and when you are trying to buy them."