UFC welterweight champion Kamaru Usman is in the thick of his preparation for his UFC 251 title defense against Gilbert Burns, and he seems to be putting in some hard rounds with a fellow titleholder.

With Usman (16-1 MMA, 11-0 UFC) and Burns (18-3 MMA, 12-3 UFC) being friends and longtime training partners in South Florida, something had to give when the pair were booked to fight for UFC gold in the main event of the July 11 card, which takes place in Yas Island, Abu Dhabi.

Usman relocated, opting to go Colorado to link up with noted coach Trevor Wittman. Of course Wittman is the head coach of interim UFC lightweight champion Justin Gaethje, who shares the same management team as Usman. All these paths have led to “The Nigerian Nightmare” and “The Highlight” becoming primary training partners for each other, and they aren’t taking it easy.

Gaethje (22-2 MMA, 5-2 UFC) posted a 15-second glimpse on social media, posting a video where he’s trading brutal body shots with Usman as he helps him ready for his upcoming fight (via Instagram):

Iron sharpens iron. How much would you pay to watch this for a few rounds? @usman84kg is looking like a straight killer. Glad to have him in the room. Just two dudes having fun 😂

Usman will attempt to make his second defense of the 170-pound title when he meets Burns. He got his reign off to a strong start in December when he stopped Colby Covington by fifth-round TKO at UFC 245.

Gaethje, meanwhile, is on the cusp of the biggest fight of his career. The interim champ is expected to meet Khabib Nurmagomedov in a lightweight title unification bout in September, though a date and location haven’t been finalized.