#2 Brock Lesnar (5-3-1)
Though his professional wrestling career began years before his MMA one, Brock Lesnar's current WWE persona (and unmatched ability to draw crowds) is directly influenced by his time in UFC.
Even his pro-wrestling ring gear - trunks and gloves, and use of a personal manager in Paul Heyman give off the aura of an elite prizefighter.
A successful Division I collegiate wrestler and NCAA Champion from the University of Minnesota, Lesnar was signed by WWE developmental in 2000 and debuted the night after WrestleMania X-8 two years later.
After becoming the youngest WWE Champion in history only five months into his start on television, he left the company in a failed attempt at joining the NFL's Minnesota Vikings franchise.
A brief and contentious run-in Antonio Inoki-ran (MMA-centric) New Japan Pro Wrestling and Inoki Genome Federation followed before Lesnar made the switch to full-fledge MMA and eventually landed in the UFC organization.
His return to wrestling in 2012, which followed his battle with an intestinal disease called diverticulitis, was under the guise of bringing "legitimacy" to WWE.
His booking since then has directly played up his successful time as a mixed martial artist, (he won the UFC Heavyweight Championship in 2008), thus Lesnar was able to leverage his fighting career into a successful second run in pro-wrestling.