The Croatian endured a difficult campaign at Goodison Park last term, scoring eight goals in 43 games.
"I think, for the most part, strikers relish competition," he told the Liverpool Echo. "It makes them work harder; it makes them strive to improve themselves every single day.
"He seems happy. I don't know whether it's because he's had a good summer or he's just happy to see us. He seems lively and raring to go."
Everton start the new Premier League campaign with a trip to Norwich City on August 17.