Rafael Carvalho is a champion who is heard even less than he's seen

Rafael Carvalho doesn't say a lot, but he's a straight shooter, as Melvin Manhoef found out in their two meetings. Dave Mandel/Sherdog.com

Rafael Carvalho has been the undisputed middleweight champion of Bellator MMA since 2015. And there's probably a decent chance you don't know a thing about him.

Carvalho (15-1) might be the most underrated champion of any major mixed martial arts promotion today. His past two title defenses took place in Italy, half a world away from his hometown of Rio de Janeiro. He has never made a single appearance on one of Bellator president Scott Coker's "tentpole" events.

He has just north of 1,000 followers on Twitter. His Instagram bio includes the hashtag #RespectTheChampion -- an ironic thing to have to remind people of.

"I promote myself in a different way," Carvalho told ESPN though a translator. "I don't talk too much. I like to show what I can do in the cage. I never trash-talk. Maybe my promotion doesn't like that too much, and that's why I don't get much attention."

Carvalho, 31, has an opportunity to change that on Friday, when he's scheduled to defend his 185-pound title against Gegard Mousasi at Bellator 200 in London. The championship fight will serve as the main event, although it was originally scheduled to co-headline.

As usual, Carvalho has not dropped any juicy soundbites leading up to the bout -- but he may not have to for this one. Mousasi (43-6-2) is considered one of the best middleweights on the planet. He left the UFC in 2017 on a five-fight win streak and then signed with Bellator as one of the sport's hottest free agents.

Carvalho, who says he wanted to be a lawyer before pursuing professional fighting, views Mousasi as the greatest challenge of his career. True to form, he says he was excited when Mousasi signed with Bellator but didn't root for him when Mousasi made his promotional debut against Alexander Shlemenko last year.

Carvalho says he doesn't care whom or where he fights. Had Mousasi lost his debut (he didn't), Carvalho would have shrugged and fought Shlemenko instead. That's just how he is.

"I was happy he signed with Bellator, because it shows where Bellator is right now -- bringing in a name like Mousasi," Carvalho said. "But I wasn't cheering for him in his first fight. I knew I would fight whoever won that night, so I wasn't cheering for either of them."

That approach typically doesn't produce high-profile fights, but Carvalho believes his body of work has him on the cusp of facing some of Bellator's marquee names. Welterweight champion Rory MacDonald has expressed interest in moving up, and Carvalho believes a fight against light heavyweight Ryan Bader is a possibility.

How ironic would it be if Bellator's most overlooked champion ended up defeating three of its most prized free-agent acquisitions? Maybe we'll get a chance to find out.

"I think Rory MacDonald is a very realistic fight," Carvalho said. "And I also see the possibility of fighting Ryan Bader. Even at heavyweight, I would do that."