UFC 203 was a mixed martial arts event produced by the Ultimate Fighting Championship held on September 10, 2016 at the Quicken Loans Arena in Cleveland, Ohio. This was a Heavyweight title fight main event card between the then Champion Stipe "Stone Cold" Miocic and his challenger Alistair "The Demolition Man" Overeem. Miocic won this contest to retain his Heavyweight title. This card was significant in that it was the Ultimate Fighting Championship professional debut of former professional wrestler and WWE World Wrestling Champion CM Punk. Punk lost his debut match in the very first round when his opponent Mickey Gall won by a submission with a rear-naked choke hold in just 2 minutes and 14 seconds.