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Kevin Mitchell scored a ninth-round stoppage win over Carl Johanneson at the O2 Arena to retain his Commonwealth super-featherweight title and add the Leeds man's British crown to his collection.

Mitchell brought a swift end to an all-action contest after clubbing Johanneson to the canvas with a short left hand then pouring on the punishment until referee Ian John-Lewis called the contest off.

It was easily the most significant win of Mitchell's 26-fight professional career but it also revealed some glaring flaws in the young West Ham man's armoury which he needs to correct if he is to go much further.

Mitchell started in style but Johanneson battled back to land a number of clean shots and was neck-and-neck on the scorecards when he ran out of gas and gave Mitchell the chance to finish matters off.

Mitchell, who had the weight of the Arena support behind him, started well and took the early stages behind a jolting left jab against an opponent who seemed to be struggling to get into his stride.

But Johanneson had started equally slowly in his last fight against Michael Gomez in October before coming back strongly to stop the Manchester man in the sixth round.

Bouncing on the balls of his feet, Mitchell continued to score with the cleaner work but the Leeds man enjoyed sporadic moments of success including a big right cross to stop Mitchell in his tracks.

Mitchell still held the upper-hand, jolting Johanneson with a left in the fifth and opening a cut around his right eye, but the momentum changed in Johanneson's favour from the half-way stage.

Mitchell touched down briefly in an all-action sixth after a right cross landed, although referee John-Lewis ruled a slip, and the pair continued to trade clean blows with Johanneson coming out on top.

Mitchell was taking far too many clean shots but was holding up admirably and came back in a strong ninth to deck the fast-fading Johanneson with a short left hand.

Sensing a sudden stoppage victory, Mitchell poured in the punches prompting a timely intervention from the referee with Johanneson still on his feet at 2.29 of the round, but offering no protest.

Mitchell told Setanta Sports 1: "I think I came of age tonight. "What a champion he (Johanneson) is. A brilliant champion. But I beat him, at 23 years of age, I knocked him out. It was a good little win for myself.

"Carl is a warrior. He is a strong man. He's demolished the British rankings but came unstuck this time. But what a fighter he is."

Mitchell added: "I had to dig deep tonight but I'm 23 and still improving. I've got bundles to learn."