Former Dallas Cowboys and Carolina Panthers defensive end Greg Hardy competed in his second mixed martial arts fight on Tuesday night at the UFC Training Center in Las Vegas, proving himself as he knocked out his opponent Tebaris Gordon within 17 seconds.

The fight took place as part of the Dana White’s Tuesday Night Contender Series on UFC Fight Pass.

Hardy is far from the first NFL player to make the jump to mixed martial arts, as former players like Herschel Walker, Matt Mitrione, Brendan Schaub and Eryk Anders all made the transition after their football careers.

Hardy’s career in mixed martial arts came about shortly after his tenure in the NFL came to an end. Drafted in the sixth round by Carolina in 2010, Hardy developed into one of the Panthers’ best defensive weapons, earning a Pro Bowl nomination in 2013 after racking up 15 sacks and 40 solo tackles.

Numerous legal issues, including a domestic violence case, resulted in the Panthers opting to sever ties with Hardy in March 2015.

The Cowboys quickly picked him up for a one-year deal, but he had to sit out the first four games after violating the NFL Personal Conduct Policy.

He finished the 2015 season with six sacks and an interception across 12 starts, but the Cowboys opted not to re-sign him due to bad behavior in the locker room.

Hardy announced in October 2016 that he would be starting a career in mixed martial arts despite having no martial arts training. He competed and won three amateur fights from November 2017 through February 2018.

Hardy made his professional debut as part of the Contender series in June, where he faced off with fellow former NFL defensive lineman Austen Lane. He won the fight in 57 seconds via knockout and was promptly awarded a UFC contract afterwards.