Birmingham City boss Alex McLeish is demanding Cameron Jerome get fitter in preseason training.

Jerome has just signed a five-year deal with Brum, but McLeish warned: "Cameron is a work in progress but I think he's definitely got the potential to cause havoc. He's as strong as an ox and as quick as a deer but I think we've still got to work on his fitness.

"He's got to go for 90 minutes. The problem with sprinters is that they use more energy when they make these lung-bursting runs, especially at breakneck speed, than a lot of others in the team.

"Therefore they can be more beneficial as an impact player or starting the game knowing that you've got to substitute them. If we can get Cameron's speed and strength into his physical attributes then he can be a huge asset."

McLeish admits that Jerome's new deal may have changed the player's attitude.

"From what I've seen in pre-season, he's showing huge confidence," said the Birmingham boss.

"Maybe it's that he sees the new contract as a bit of belief in him from the club's point of view. He maybe felt his contract needed to be changed and rewarded.

"I thought he had a good season last year. He'll be frustrated at not starting all the games but my challenge to him is to get the superb fitness that goes with being a top Premier League player. Cameron is only 22. It's four or five years until strikers like him peak."