Harrison has lost two of his 21 pro bouts

Harrison, 34, was dismal in dropping points decisions to fellow Londoner Danny Williams last December and American Dominick Guinn last month.

But Leonard told BBC Radio Five Live: "There's nobody in the heavyweight division. If Audley stays serious and focused, he can make a difference.

"But if he doesn't win his next fight impressively, he should get a new job."

Harrison switches to new trainer

Last week, Harrison announced he has teamed up with highly-respected American trainer Buddy McGirt in a bid to revitalise his ailing career.

And the 2000 Olympic super heavyweight champion said he was not considering retirement in the wake of back-to-back defeats.

"When I first saw Audley Harrison, I thought 'here's a top prospect for the heavyweight division'," said Leonard, a five-weight world champion.

"He has the whole package - he's charismatic, he's big, he's strong. But he needs to start being a fighter and not a talker."