DeGale, winner of a middleweight gold at the 2008 Olympic Games in Beijing, produced a superb performance to claim victory by virtue of a unanimous points decision to seal an historic triumph.

The 29-year-old Briton started brightly and had Dirrell on the canvas in just the second round but the American, keen to impress on home soil, rallied and fought his way back into the contest.

He managed to land several decent punches on DeGale, who appeared to be tiring as the bout went on, before the British fighter launched a late attack and was given the win on the judges’ scorecards.

It marked a fantastic night for the Londoner who has often been much-maligned for his lack of success at world title level and he claimed he now feels he can take on anyone in the super-middleweight division.

“It's an unbelievable feeling, I'm world champ - I made history,” DeGale said.

“I will take on any super-middleweight in the world.

“I’m hard to beat when I’m at my best.

“Dirrell is a very good opponent and he’s very talented.

“If anything it’s me and him second and third in the rankings.

“Andre Ward’s there and there’s me and him.”

The victory for DeGale sees him move onto a professional record of 21 wins and one defeat and his success in Boston has already led to rumours of a potential rematch with George Groves.

The two were involved in a bitter feud in the lead-up to their contest back in 2011, a contest won by Groves and that loss remains the only blemish on DeGale’s record.

The Briton appeared keen to prove a point from the outset as he knocked Dirrell to the floor with a well-directed overhand left with the bout barely two rounds old.

But the 31-year-old American recovered and looked the more dangerous of the two boxers as the fight went on, with DeGale perhaps intent on defending his lead rather than extending it.

It was a tactic that paid off however as a late spell in which he displayed some of the shots he had managed to land in the earlier rounds  was enough to give him a memorable win and with it the first professional world title of his career.

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