Two-division UFC title holder Daniel Cormier doesn’t plan on stepping inside the boxing ring unless it’s to spar for a mixed martial arts bout.

Cormier is riding a wave of momentum just before his planned retirement. “DC” is the reigning UFC light heavyweight and heavyweight champion. He’s undefeated as a heavyweight and has only lost to Jon Jones at 205 pounds. After knocking out Stipe Miocic to capture the heavyweight gold, Cormier defended his title against Derrick Lewis at UFC 230. Cormier retained his championship via second-round submission.

Cormier recently appeared on the MMA Junkie Radio Show. “DC” explained why he’s ruling out a transition to boxing:

“I mean, why would I want to go and fight these guys in a singular sport. I don’t want to go try to fight some dude in the sport that he’s best at. That’s like me asking Anthony Joshua to come and try to wrestle me or fight me in a mixed martial arts contest. He’d have no chance, just as I would have no chance (boxing) against Anthony Joshua. I don’t want to do that for nothing. I’m not going to do that for nothing.”

We’ve seen MMA fighters make the transition to boxing and vice versa. Conor McGregor was stopped by Floyd Mayweather in the 10th round via TKO in a boxing match last year. Back in Aug. 2010, multiple-time boxing world champion James Toney was submitted by Randy Couture at UFC 118. Mayweather is set to take on kickboxing and MMA international sensation Tenshin Nasukawa at Rizin 14. A rule set has not been determined.