The Pompey boss said: “He is a fantastic player. He is starting to score a few and his work rate is tremendous.
“It takes time for players to settle when they come from abroad. Didier Drogba was struggling last year and look at him now. Michael Ballack has been fairly quiet as well.
“You never want to write players like Shevchenko off. He looks a great lad to me and a fantastic professional.”