Sean O’Malley stunned Aljamain Sterling with a second-round stoppage to claim the bantamweight title at UFC 292 in Boston, Massachusetts.

The 28-year-old O’Malley landed a perfect counter-right hand, dropping fellow American Sterling before ending the contest with punches on the ground, according to BBC Sport.

The victory has completed an impressive ascension for O’Malley, who has become one of the UFC’s most marketable stars.

“This was the most nervous I’ve ever been for a fight,” said O’Malley.

“Aljamain is the best bantamweight of all time, so yeah, I was nervous, but I never lost the confidence because I know what I possess – this right hand, baby.”

O’Malley was granted his title shot after a narrow win over Petr Yan in October, which was his eighth in 10 bouts since earning a UFC contract after impressing on reality TV show, Dana’s White’s Contender Series.

But Sterling, 34, who was making the fourth defence of his title, had argued pre-fight O’Malley did not deserve the opportunity and he had been fast-tracked into the bout because of his popularity.

O’Malley, who was competing in his first UFC title bout, was cheered by the Boston crowd on his way to the octagon while Sterling embraced heavy boos as he smiled and gestured towards the television cameras.