O’Neill said: “Carew is better than a decent player.
“If he can stay fit, he will be a decent acquisition to us and I have been very encouraged in the three games so far.
“It is very early but the crowd have taken to him. He is 27 and I don’t see why he should not be reaching his peak at Aston Villa.
“Villa have had some fabulous centre forwards over the years without a doubt. I think back to my friend Peter Withe, whom I played with at Nottingham Forest, and he was one of them.
“If John does half as well as Peter Withe, I’ll be happy.
“He proved himself in Spanish football (with Valencia) but he wanted to compete in the Premiership.
“I think he can adjust to the Premiership and it has been a positive start.
“He suffered from a touch of cramp in his first two games after not playing for some time but got in 90 minutes at Reading which will be good for him.
“The good thing is that during the last three games, we have looked capable of scoring.”
