Samoa Joe Brock Lesnar WWE
(L-R) Samoa Joe, Brock Lesnar and Paul Heyman in a promo segment on Monday Night Raw.WWE

Brock Lesnar is set to defend his WWE Universal Championship in a fatal four-way match at SummerSlam on Sunday, 20 August. He'll take on Roman Reigns, Braun Strowman and Samoa Joe at the event, and will leave the company if he loses the title.

He won't really leave the company, that's just a storyline. Lesnar is contracted to work for WWE through until Wrestlemania 34 next April, but he may be taking the rest of the year off to train for a return to MMA.

Lesnar appears to be heading for a clash with UFC Light Heavyweight Champion Jon Jones, after the latter called him out following his title win at UFC 214 this past weekend (29 June).

Should he be dropping the Universal title at SummerSlam, any one of his opponents could be the one to win it – but a new report claims it's Samoa Joe who Lesnar's storyline manager Paul Heyman wants to win the match.

Sports Illustrated reports that Heyman is advocating for a Joe win, after he fought and lost to Lesnar at last month's Great Balls of Fire event. It's been said that Brock enjoyed working with Joe.

The report also cites the possibility that Smackdown's Baron Corbin may cash in his Money in the Bank contract (which grants him a title opportunity anytime, anywhere) for the Raw-brand championship.

WWE legend Jim Ross described Lesnar's return to MMA and UFC as "inevitable" in a blog last week, and after Jones called Brock out it seems that's the match being worked towards.

In another blog, Ross said of the potential superfight: "This main event gives UFC a 'hit,' without question, while they await other stars to either return to form or continue to evolve as legit, PPV selling main eventers."

Jones would be moving up a weight class to take on Lesnar, but the latter would certainly need to train hard to be able to compete with the lanky 30-year-old, whose MMA record stands at 23 wins and one loss via disqualification.

Lesnar's record sits at five wins, three losses and one no-contest. That no-contest came against Mark Hunt last year at UFC 200, after Lesnar's original win was overturned following the failure of a drugs test.

Lesnar will next appear WWE's SummerSlam, but he has also been advertised for the No Mercy event in September. This could very well change however.