6. Jon Jones | UFC Light Heavyweight -- 1,501 Days
Had Jones not run afoul of the law, most believe he would still be sitting atop the UFC’s 205-pound mountain. He had already beaten his two most significant threats: Alexander Gustafsson and Daniel Cormier. However, Jones began to unravel soon after his victory over Cormier at UFC 182.
Jones tested positive for cocaine and was later involved in a hit-and-run accident in Albuquerque, N.M. Marijuana paraphernalia was recovered from the vehicle he was driving, and a pregnant women in the car he struck suffered a broken arm. Jones was subsequently stripped of the UFC light heavyweight championship and suspended indefinitely. “Bones” had successfully defended the title eight times, with wins over Cormier, Gustafsson, Glover Teixeira, Chael Sonnen, Vitor Belfort, Rashad Evans, Lyoto Machida and Quinton Jackson. Jones was on his way to possibly becoming the greatest mixed martial artist of all-time, but his behavior outside the cage put that kind of legacy building on hold. The 28-year-old is expected to return sometime in the first half of 2016.
Number 5 » Fedor Emelianenko