James DeGale vows to make history against Andre Dirrell

James DeGale (right) says he is "obsessed with making history"

James DeGale has vowed to become the first British boxer to win Olympic gold and a professional world title when he fights Andre Dirrell for the vacant IBF super-middleweight belt on Saturday.

Londoner DeGale, 29, fights 31-year-old American Dirrell - whose only defeat was by Carl Froch in 2009 - in Boston.

"I'm obsessed with making history," said DeGale, who became Olympic champion in Beijing in 2008.

"He's tricky, talented and confident but I'm doing it for my country."

Both men made the weight on Friday, with DeGale scaling 167.2lb, 14 ounces under the limit, and Dirrell 167.8lb.

Dirrell had plenty to say at the traditional stare-down, while his brother, Willy, flung insults at DeGale from the wings.

"He kept telling me that it's serious now," said DeGale. "I said to him: 'Don't you think I know that?' It's serious for him because I'm going to do this."

Dirrell has 24 wins from 25 professional fights, his one defeat coming against Britain's Carl Froch in 2009

The Massachusetts boxing commission was keen to appoint its own judges but DeGale's promoter Eddie Hearn successfully argued for one Englishman, one American and one neutral official.

The choice of judges offsets home advantage for Dirrell, which his advisor Al Haymon ensured by offering in excess of $3m (£1.94m) to host the fight.

However, the arena is unlikely to be filled to its 8,000 capacity, with the fight scheduled to start at 16:30 local time for the benefit of American television.

Seven British men have struck Olympic boxing gold since World War Two but none of them have gone on to win a world title in the paid ranks.

Chris Finnegan won Olympic gold in 1968 and fought for the world light-heavyweight title in 1972, losing to the great Bob Foster.

Audley Harrison won gold in 2000 but was knocked out by David Haye when he challenged for his fellow Briton's WBA heavyweight title in 2010.

"It's a chance that I can't let slip," said southpaw DeGale, whose only defeat in 21 pro fights was by George Groves in 2011.

"People aren't going to give me opportunities again, because I'm too good - no-one is going to fight me for a voluntary defence."

Since losing to Froch in controversial circumstances in Nottingham six years ago, Dirrell, also a southpaw, has improved to 24 wins and one defeat.

"I'm much hungrier than I was early in my career and more focused mentally," said Dirrell.

"He feels like he's an undefeated fighter, I feel like I'm an undefeated fighter. But we both have a lot to prove. I know I'm faster. I know I'm smarter and I know I'm a better boxer. It's just as simple as that."

Victory for DeGale could lead to a rematch with Groves, who is expected to challenge Sweden's WBC champion Badou Jack later this year.

Froch has already ruled out a match with DeGale and is reported to want one last fight, against middleweight king Gennady Golovkin, before retiring.