BRYANT JENNINGS believes he will cause one of boxing's greatest ever upsets this weekend.

Klitschko V Jennings

The American becomes the latest man attempting to topple IBF, WBA and WBO heavyweight champion Wladimir Klitschko in their BoxNation televised clash at New York's Madison Square Garden on Saturday night.

Klitschko will be making his 18th world title defence in his second reign as champ, and only Joe Louis has ruled longer.

Louis was the heavyweight king for over 11 years. Klitschko celebrated his ninth anniversary as champ on Wednesday.

That's when he stopped Chris Byrd in seven rounds to claim the IBF portion of the title.

Jennings, 30, who was three years from taking up boxing when the Ukrainian beat Byrd, but insists an upset is on the cards and that Klitschko's vast experience counts for nothing.

"Experience plays a part, but not a big part, because we've seen situations where the less experienced guy comes out on top," said Jennings who has won all 19 professional contests.

 "I don't play that experience game, because everybody who I've faced has been more experienced than me. I first put on gloves six years ago and here I am, fighting for the heavyweight championship of the world."

The lifestyles of Klitschko and Jennings are the polar opposite.

The champion lives a millionaire's life at various homes in Germany, Ukraine and United States and his partner is Hollywood actress Hayden Panettiere.

Bryant Jennings In Action

Jennings still works as a maintenance man at a Philadelphia bank, although he has taken time off to train in Houston for his chance of a lifetime, and he's a threat Klitschko take seriously.

Wladimir who is likely to face Lancashire traveller Tyson Fury in September if he wins this weekend says, "Bryant Jennings is fighting for a lot.

He is fighting for his pride, but he is also fighting for a lot of financial assets. It is an opportunity to literally change the life for yourself and your family.

"I'm not going to underestimate him by any means. I'm not going to overestimate him by any means because as I said, we're all limited, including myself.

Bryant Jennings And Wladimir Klitschko

"So we can just fight in the way we can fight and I think that it's going to be an exciting fight.

"Why? Because Bryant Jennings is pretty much at home. He's going to have a lot of support in the arena and he's highly motivated. He's very energetic and he's very athletic.

Klitschko's domination has been a turn-off for many American fans and this is his first fight in the USA since outpointing Sultan Ibragimov, at tomorrow's venue in 2008.

He has promised to impress and show that challengers like Tyson Fury and WBC champ Deontay Wilder still have some way to go.