UFC middleweight title champion Israel Adesanya will defend his 185-pound title against Paulo Costa on September 19.

The fight, which will take place at UFC 253, doesn’t have a location yet. It probably will take place in either Las Vegas or Abu Dhabi, but the promotion hasn’t finalized those plans just yet because of the coronavirus pandemic, sources said.

The duo have been entangled in a war of words since before Adesanya won the middleweight title in October.

The fight will mark just the second time in UFC history that two undefeated males fight for an undisputed title. The first time was back in 2008 when champion Rashad Evans defended the light heavyweight title against Lyoto Machida at UFC 98.

Costa tweeted on Sunday, “The fight is on folks!” News of the fight was first reported by Combate.

Adesanya (19-0) successfully defended the middleweight title for the first time in March when he defeated Yoel Romero via unanimous decision. That fight was supposed to be against his bitter rival, Costa, however, Costa was forced out of the fight after suffering a torn left biceps.

Costa (13-0), from Brazil, most recently defeated Romero via unanimous decision in August 2019.