Undefeated Russian Murat Gassiev defends his International Boxing Federation cruiserweight crown against Poland's Krzysztof Wlodarczyk on Saturday in a quarterfinal bout of the World Boxing Super Series tournament.

The winner of the 12-round matchup at Newark, New Jersey, will take his title into a unification showdown early next year against the World Boxing Association champion, undefeated Cuban Yunier Dorticos, 22-0 with 21 knockouts.

"This is an exciting tournament with four world champions. It's a great opportunity for all the fighters," Gassiev said on Thursday. "This is the best way to unify titles and show everyone I'm the best cruiserweight in the world."

Gassiev, 24-0 with 17 knockouts, makes his first defence of the crown he took last December with a split-decision triumph over Russian southpaw Denis Lebedev at Moscow.

"To be a champion and defend my belt is something I always dreamed of," Gassiev said. "I want to stay in this position for a long time."

"When we faced-off I looked inside his eyes and saw that he is very serious. He's ready for a big fight and I will make sure this is a great fight on Saturday.

"This is someone who earned his chance to fight me. I will always challenge the best in the division no matter who they are."

Wlodarczyk, 53-3 with one drawn and 37 knockouts, tries to reclaim a crown he owned for six months in 2007. The 36-year-old Polish fighter, 12 years older than his rival, also held the World Boxing Council cruiserweight title from 2010 to 2014.

"I'm going to have to be at my best and I feel I will be," Wlodarczyk said. "I have to be the smarter fighter in the ring. I think I can take advantage of my experience by staying smart and making the better adjustments. I'm going to be ready for anything Gassiev throws at me."

World Boxing Council champion Mairis Briedis (23-0, 18 knockouts) of Latvia will face World Boxing Organisation champion Oleksandr Usyk (13-0, 11 knockouts) of Ukraine, the 2012 London Olympic heavyweight champion, in the other semifinal.