Diamond joins the UFC as a bit of an enigma in mixed martial arts, with a 3-0 record and those wins coming by submission, knockout and decision. Like many on the local circuit, finding fights in MMA has been a difficult task, particularly since the Covid-19 pandemic took hold of the world.
While he has been able to stay active on the local kickboxing scene, his last MMA bout came in February of 2020, when he beat Australian Dimps Gilles by unanimous decision at Eternal 50 in Auckland.
But while some time has passed since he was last in the cage, Diamond has been active on the local kickboxing scene, and said that combined with training at City Kickboxing will have him more than prepared to compete.
"Look at our team; we are the best in the world. The way I see it is I just have to train hard, listen to my coaches," Diamond said.
"I'm just going to get in there, work my ass off and work as hard as I can. When I get into that cage, I'm just going to put on the best performance I can. I know I'll be ready. Not having an MMA fight for a while doesn't change a thing.
"All I can do is do me. For me to get to the UFC, it's me doing what I do best. My formula works; it's been working for a long time. I just have to keep with the same formula and that's going to show my success and how my career is going to go. I just have to be me."
Zimbabwean-born Diamond will be joined by City Kickboxing teammates Carlos Ulberg and Israel Adesanya at UFC 271, with Ulberg taking on Fabio Cherant and Adesanya putting his UFC middleweight title on the line against Robert Whittaker in the main event.
In Cosce, Diamond faces an interesting stylistic matchup for his debut as the American looks most comfortable when he is able to control the bout with his wrestling. That could be tough to do against Diamond, whose style of striking feeds into his enigmatic persona.
But while it will be his first bout with the world's leading MMA promotion, Diamond isn't thinking too far ahead.
"For me, the excitement comes when they cage is actually locked and the bell rings. Between now and then, I'm not sure what could happen. So, I'm praying for the best; that he comes out healthy, I come out healthy and we meet in that cage.
"For me that's the most exciting thing: the cage is locked, the bell rings and that's us."