'She remains a phenom': Ronda Rousey taps out Gina Carano, wins comeback fight in 17 seconds

Ronda Rousey's comeback to mixed martial arts ended exactly as she predicted, making Gina Carano submit in 17 seconds in trademark fashion.

After a decade away from the sport, Rousey took her rival to the ground straight away before locking in an armbar and forcing Carano to tap out.

The pair hugged and embraced straight after the fight was over.

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"She remains a phenom," Mauro Ranallo said on commentary for Netflix.

Rousey hadn't fought since late-2016 after losing back-to-back UFC title fights against Holly Holm and Amanda Nunes, with few expecting her to ever return to the cage, while female pioneer Carano hadn't competed professionally since 2009.

The 39-year-old was asked after her return victory whether she would continue fighting, but made it clear the Carano fight would be her last.

"There's no way I could've ended it better than this," Rousey said.

"I want to make some more babies."

Rousey made an estimated $3.1 million AUD for main eventing the fight in Los Angeles, with Carano earning $1.5 million despite the very quickdefeat.

In the co-main event, cult hero Nate Diaz was completely covered in blood during his bout with Mike Perry, forcing his corner to wave off the bout.

"This is a horror show," Ranallo said.

Former UFC heavyweight champion Francis Ngannou won his fight against Brazilian opponent Philipe Lins via first-round knockout.

Ngannou floored Lins with a brutal overhand right hand that immediately stopped the contest with 30 seconds left in the opening round.

After the win, he called out Jon Jones - who was sitting on the broadcast panel - for a potential showdown in the future.

Jones admitted he would be open to fighting Ngannou, but conceded his current UFC contract status could make things tricky.

"I've got to try to focus on getting out of my UFC contract," he said.

"That's going to be the difficult part if this fight is going to happen. I don't think Dana [White] is interested in doing business with Francis.

"If we can get out of my contract, that would be great."

Ngannou also said he would be keen to take on Jake Paul - the promoter of the Netflix event on Sunday (AEST) - in either boxing or MMA down the line.