"When he first arrived here he didn't get in the team right away. That can sometimes happen as you saw with Nani and Anderson earlier this season. It can take time to adapt.
"But once Michael started playing alongside [Paul] Scholes it really helped him. He really matured when Scholes was out injured and he's developed very well.
"The challenge of coming to Manchester United was a good one. He's playing with a squad of really good players which always helps. And you've seen this season a player reaching the top of his game."