WWE falls into the category of 'Sports Entertainment' which means that although professional wrestling is a part of the show, the show is mostly meant to tell a story more being a legitimate competition. Matches are scripted as wrestlers are informed about a storyline much in advance. It is usually very rare for professionals from other combat sports to be involved in the WWE. However, exceptions exist as we take a look at those five athletes from disciplines such as boxing and Mixed Martial Arts (MMA) who entered the WWE ring.
The two-time UFC Heavyweight Champion entered the WWE on last week's Friday Night SmackDown and gave Brock Lesnar a beating on behalf of the injured Rey Mysterio. The two may face-off at the Crown Jewel PPV which will happen later this month, but nothing has been announced yet by the WWE. Their rivalry goes back all the way to 2010 when Velasquez annihilated Lesnar for the UFC Heavyweight Championship.
The English boxer made his way to the WWE on the Fox debut of Friday Night SmackDown last Friday where he watched the matches from the sidelines. During his match, Braun Strowman teased Fury and then ended up tossing Dolph Ziggler towards Fury. A startled Fury jumped over the barricade ready to brawl with Strowman. The officials contained them but the two brawled on this week's episode of Raw and things got ugly. The two may also face off at the WWE Crown Jewel Event.
Mike Tyson entered the WWE in the late 90s and ended up joining D-Generation X. Tyson, who was a special referee at the Wrestlemania XIV, knocked out Shawn Michaels as Stone Cold Steve Austin won the title. Tyson also reunited with DX in a special segment in 2010.
Mayweather was a part of the WWE in 2008 as he feuded with the Big Show after the 7-foot monster bullied Mayweather for his size. Mayweather punched Big Show and left him with a bleeding nose. The two faced off at Wrestlemania XXIV where Mayweather used brass knuckles to knock out the Big Show and win the match.
Wade Barrett has been in the WWE under various gimmicks but the former leader of the Nexus was a bare-knuckle boxing champion in Europe. Barrett fought a lot of fights in his early twenties and won a heavy cash prize at a fight he took part in. He was later attacked by a thief who attempted to rob him of the money but was unsuccessful.