UFC's Kamaru Usman Calls Out Georges St-Pierre, 'Where You At?!'

Kamaru Usman wants a shot at the legend -- telling TMZ Sports he's officially campaigning for a fight with Georges St-Pierre!

"Right now, we're tied for the record -- most consecutive wins in the welterweight division," Usman says ... "[He's] considered one of the best and that's where I aim to be."

Of course, there's just one problem ... 39-year-old GSP retired a few years ago. But, there have been rumblings that he's down for a comeback -- and what better way to return than for a shot at the welterweight champ!

"George can still do it," Usman says ... "He proved it 2 years ago when he came back that he can still do it. I feel that he's still able to do it, I feel like he's still able to come in and be that opponent where people are unsure like, 'You know what, we don't know if Usman's got this one.' And I think Georges St-Pierre can be that guy."

Usman is coming off a dominating victory over Jorge Masvidal -- and before that he beat up Colby Covington and then-UFC champ Tyron Woodley. So, he's looking for another high-profile challenge.

"Where you at Georges? Where you at," Usman joked ... "Haha nah, George knows what he's done with his legacy. He's cemented his legacy."

"I would love to test myself. I'm a martial artist just like he was a martial artist and if he still has some fire burning in that oven, let's test it out!"

There's more ... we also asked Kamaru about that friendly moment with Masvidal after their fight at UFC 251 -- are they friends now?

"I wouldn't say all that. I would say it's a respect."

"He's a martial artist, I'm a martial artist, we respect one another because we share that space with one another. It's pretty difficult not to respect one another after you shared something so intimate with one another. I think that's what it was."

And, while Usman says he's deadly serious about wanting a fight with GSP, he's also serious about fighting ANYONE the UFC puts in front of him.

"I don't discriminate when it comes to an opponent and that's one thing that the company -- you can quote me on that, I don't say NO to anybody."