Season 4

A popular fighter who won the second season of The Ultimate Fighter, Joe "Daddy" Stevenson fought the likes of BJ Penn and Nate Diaz during his 16-fight career in the UFC. But his greatest battle came after his run in the Octagon, when a deep depression and alcoholism threatened to derail his life.

Before Conor McGregor, Irish MMA found a hero in fiercely proud Irish-American Marcus Davis, a 15-fight UFC veteran who was always in a good scrap. Sharing a day in his post-retirement life as a coach and gym owner, Davis reflects on his memorable UFC run and how he is adjusting to contributing to the sport outside of the Octagon.

Tim Sylvia fought a who's who of his era, including Frank Mir, Randy Couture and Minotauro Nogueira. The two-time UFC heavyweight champ reflects on his fighting career and his new roles as a hunting show presenter, development contractor and father.

With the distinctive dyed blue hair and unforgettable story of drawing courage from his son's battle with brain cancer, Haynes struck a memorable character during the third season of The Ultimate Fighter in 2006. Seven years on from his final MMA fight, Haynes has moved on from the sport completely.

With a unique mix of submission and striking skills, Brazilian Marco Ruas is undoubtedly one of the progenitors of modern mixed martial arts. Now 57-years-old and living in California, the Luta Livre legend says he is at peace with this fighting legacy.

A cast member of the 'comeback' season of The Ultimate Fighter over a decade ago Spratt, still in shape at 46-years-old, is planning a final bout in 2017 while also focusing on teaching MMA, a music career and fatherhood.