"Our fans have played a major part for us so far this season - home and away - so there is more to come," said Crouch.
"I don't think anyone expected to see Milan at Fratton Park but we can make it difficult for them, get the supporters behind us and hopefully that might give us an edge to cause a surprise.
"The changing rooms are a bit smaller than most, but after Thursday Paolo Maldini can say he has now done it all."
Crouch added: "They were expected to be in the Champions League and it is a fantastic challenge for us. The fact we are playing against teams like this and testing ourselves against the best in the world is a credit to what the club has achieved."