Alexander Povetkin beat Ruslan Chagaev on a unanimous points decision to win the WBA's 'regular' heavyweight title.
Wladimir Klitschko, who recently defeated David Haye in his heavyweight unification bout, is the WBA 'super' champion but now Povetkin has a belt of his own after his victory in Erfurt, Germany on Saturday night.
The former Olympic champion dominated the fight against the former champion in the final stages and was awarded the win 117-113 twice and 116-112 on the scorecards.
Chagaev enjoyed success in the sixth and seventh rounds but it wasn't enough to stop him falling to a second career defeat.
"I'm sorry, today was not my day," said Chagaev, whose health problems have hindered his career in recent times. "He's a good boxer, a real world champion now."
Povetkin (21-0) has been protected by his handlers despite earning victories over the likes of Chris Byrd and Eddie Chambers more than three years ago, but is now one of few legitimate challengers to the Klitschkos.
"My father always hoped and wanted for me to be a world champion," said the Russian, who lost his dad last year.
"It was a very hard fight. It was very hard to fight him. I have a lot of respect for him, he's a very difficult and patient boxer."