By Sanjeev Shetty

BBC Sport looks at five men with a chance of taking over at the top of the heavyweight division.

Wladimir Klitschko

Nothing sells in boxing like a white heavyweight - for further evidence, please see the career of Gerry Cooney, an Irish American with a big punch but little else who got a shot at the world title.

Klitschko has the power and charisma to be the next big thing, but his chin and stamina have let him down in his two career losses.

But with the standards at the top of the division slipping - 40-year-old Evander Holyfield and 36-year-old Mike Tyson are still dangerous - the 27-year-old Klitschko still has a chance.

Relatively unknown until he beat Danny Williams and Julius Francis in the space of two months, the rotund German-based Turk may be a lot better than he looks.

A former world amateur champion, Sam has been European title holder since the turn of the year and looked impressive in his fight with Williams.

The question mark over him is his conditioning - he has not been 12 rounds as a pro and his ample gerth suggests that he may not be the most dedicated of trainers.

Audley Harrison

Do not laugh - it is very possible that Harrison could be the next big thing.

If being heavyweight champion of the world was based on vocal ability, Harrison, unbeaten in 11 fights, would already be king.

And despite all the negative press that surrounds the 2000 Olympic champion, he continues to make the headlines, even if his fights have hardly set the world on fire.

In an era where a fighter does not have to fight the best to be considered the best, Harrison could well find himself fighting for the sport's richest crown.

Dominick Guinn

The unbeaten American has been plying his trade around the small club circuits but is now ready to be taken very seriously.

With a record of 21 wins and 16 KOs, Guinn has been moved cautiously since turning professional and he outlined his credentials when he hammered former world title challenger Michael Grant in seven rounds.

Trained by Ronnie Shields, one of the top cornermen in the business, Guinn can look forward to a prosperous career.

Calvin Brock

The 28-year-old has had 14 fights and has won all of them.

He was part of the underachieving US Olympic team in 2000 but has put his Sydney disappointments behind him since to make an impressive start to his career.

A well-proportioned 235lbs, Brock should receive the necessary exposure and hype to get him to the next level - after all, it has been a long time since an American has been considered the best heavyweight in the world.