Russian boxer Artur Beterbiev (pictured) claimed his first world title belt with a 12th round knockout of Enrico Koelling in a battle for the vacant IBF light heavyweight crown

Fresno (United States) (AFP) - Russian boxer Artur Beterbiev claimed his first world title belt on Saturday with a 12th round knockout of Enrico Koelling in a battle for the vacant IBF light heavyweight crown.

The undefeated Beterbiev recorded his 12th straight knockout but he had to go past seven rounds for the first time in his career to get the 175-pound belt.

The 32-year-old Beterbiev systematically dismantled underdog Koelling over 12 rounds, finishing him off with a right hook to the head with 27 seconds left in front of a crowd of 18,800 at the Fresno State University arena.

He knocked Koelling down for the first time in the fight earlier in the round but the 27-year-old German was able to continue after an eight count from the referee.

Beterbiev improved to a career record of 12-0 with 12 knockouts after just his second pro fight outside of Canada, where he trains.

Beterbiev had over 300 fights in an impressive amateur career that included two victories over former light heavyweight champ Sergey “Krusher” Kovalev.

As a pro, Beterbiev had only been past four rounds once when he was pushed to the seventh round by Alexander Johnson in 2015.

Koelling landed very few good punches in the one-sided fight but he can find solace in becoming the first fighter to survive into the 12th round with Beterbiev who some call the best pure puncher in boxing today.

With his first world title in hand there are some who now feel the two-time Russian Olympian is on the verge of finally fulfilling the lofty expectations he had coming out of the amateur ranks.

Beterbiev moved to Montreal when he turned pro and signed a contract with promoter Yvon Michel. Beterbiev and Michel are now embroiled contract dispute which is in the Canadian courts.

This was just the second career loss for Koelling who had won seven in a row since a 2015 defeat on points to Italian Mirco Ricci.

Koelling (23-2) was hoping to become the first German to win a world title in the US since Max Schmeling won the NBA – now the World Boxing Association – world heavyweight title at Yankee Stadium, New York, in June 1930.