© Getty Images Enlarge Wladimir Klitschko beat Alex Leapai a fortnight ago

Less than two weeks after heavyweight champion Wladimir Klitschko smoked Alex Leapai in a one-sided fifth-round knockout victory to retain the title for the 16th time, he was ordered to make a mandatory defence.

Klitschko (62-3, 53 KOs), 38, of Ukraine, has a mandatory due against Kubrat Pulev of Bulgaria, and on Thursday it was ordered by the IBF.

Pulev, who turned 33 last week, became the mandatory challenger in August when he outpointed American Tony Thompson in a final elimination bout in Germany. Pulev (20-0, 11 KOs) has fought twice more since, winning both by knockout, while waiting for the title fight to be ordered.

"That's what I call a late birthday gift," Pulev said in translated comments. "I was ringside when Wladimir defended his belts a few weeks ago. It was a walk in the park for him against Leapai. When Klitschko meets me inside the ring, I will cause him real problems, to say the least. I will show the fans worldwide that Klitschko is no invincible machine and fulfill my dream."

Kalle Sauerland of Sauerland Event, Pulev's promoter, said he is talking with K2 Promotions, Klitschko's company, about making the fight.

"The negotiations with Team Klitschko have already begun," he said. "We are excited to present a heavyweight bout in cooperation with K2, which is deserving of its heavyweight world championship status."

The sides have until June 5 to make a deal, or a purse bid will be ordered. However, if the camps are close they can request -- and most likely would receive -- a brief extension of the deadline.

There also is a chance that Klitschko could put off the fight for one more bout if his representatives are able to make a deal for a unification fight against the winner of the rematch between Bermane Stiverne and Chris Arreola, who meet on Saturday night (ESPN, 8 ET) in Los Angeles for the belt vacated in December by Vitali Klitschko, Wladimir's older brother.

Klitschko, who owns three of the major sanctioning organization titles and also is the lineal champion, would like an opportunity to unify the four major belts and win the one that he has never held, because his brother had it for so many years. IBF rules allow for unification fights to take precedent over mandatory fights.

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