Tenshin Nasukawa accepted Conor McGregor's invitation to fight, but there are a few stipulations. 

After McGregor tweeted out that he would like to fight the champion kickboxer in an MMA match, Nasukawa said that he's open to the fight if McGregor is willing to drop to his weight class.  

"Dear Mr. McGregor. Thank you very much for remembering my name. I’m honored that you would even consider fighting me," he wrote. "58 kg, kickboxing rules would probably get us in the ring sometime in the near future. I will fight my RISE world GP this year so please watch your diet and wait for me!"

The rules came after McGregor reached out to UFC on Twitter to try and arrange a fight with the kickboxer.

"I wish to go to Tokyo to face Tenshin Nasukawa in a Mixed Martial Arts exhibition bout," he wrote. "Before this summer. Please arrange this, this instant."

The fight between Nasukawa and McGregor would complete a fighting triangle between the three fighters of different disciplines. Conor is an MMA fighter, Nasukawa is an undefeated kickboxer, and Mayweather is a boxer. Mayweather beat both McGregor and Nasukawa in boxing matches, the latter handily. It seems like Nasukawa learned that lesson, putting it out there that he would only fight under kickboxing rules.