Ryan Roberts suffers knee injury, retires after TKO loss to Rob Emerson at Victory FC 54

Ryan Roberts will have more hurdles to cross in the coming months.

A UFC veteran who endured through a series of tragic circumstances over the past three years, Roberts suffered a first-round TKO loss due to a knee injury in the co-main event of Victory FC 54 on Friday night, falling short in his bid for the vacant Victory FC featherweight title against Rob Emerson in his hometown of Omaha, Nebraska.

Roberts, 38, was returning to the fight game for the first time since a rare bacterial infection nearly took his life this past spring. But it wasn't meant to be, as the longtime Omaha veteran ate a nasty straight right that sent him reeling awkwardly across the cage. Almost instantaneously, Roberts turtled up clutching his right knee in pain, forcing the referee to rush in and stop the contest at 1:34 of the opening round.

Afterward, Roberts revealed that he suffered a torn ACL last week in training, but was intent on competing against Emerson regardless. Then, he announced his retirement from mixed martial arts.

"This obviously didn't go my way. Hats off to Rob, he fought one hell of a fight," Roberts said. "I came out, I really pushed through. I actually ended up tearing my ACL last Friday night in practice, and tried to ice, tried to get it (right), thinking I was going to be able to come in here and still compete with the guys at his level. And that wasn't the case.

"The reason I pushed so hard is, this was my last fight. I'm retiring after tonight. I'm going to focus on my family. But I appreciate all of you guys supporting me all of the years. Everything I've been through, you guys have always had my back. From the bottom of my heart, thank you Omaha. You have made this an awesome sport, not just for me, but for all of the other athletes coming up."

Roberts (21-12-1, 1 NC) has overcome a lot over the past several years. In 2013, his sister Andrea was murdered as part of a four-victim spree by serial killer Nikko Jenkins. A year later, Roberts' mother fell into a coma due to a rare bacterial infection and ended up requiring all four of her limbs to be amputated in order to save her life. Then, this past autumn, Roberts nearly died at the hands of an equally rare bacterial infection that he contracted while cornering a teammate in Grozny, Russia.

Through it all, Roberts has remained positive and continued moving forward with his life. He was the subject of a profile published Friday on MMA Fighting.

"Things don't just go away. But if you stay persistent, if you keep trying, even after you're told no, you keep trying, keep trying to do the next right thing, eventually it will start working out," Roberts told MMA Fighting. "It probably won't be near as fast as you want it to, but eventually it will all work out. And for me, I just keep living my life that way, man. Just keep trying to do the next right thing."

As for Emerson, the victory pushes the former TUF 5 cast member to a record of 7-1 since 2012, with six of those victories ending via stoppage. The win also sees Emerson crowned as a two-division Victory FC champion, as he now owns the promotion's bantamweight and featherweight titles. Following his performance, the 35-year-old MMA Lab product made a plea for the UFC to give him a second chance.

"It's been seven years since I've been in the big show. What do you guys think? Bring me home," Emerson said. "I think I can go tear up that bantamweight division. There's a lot of tough guys over there I think I can knock out, and put on some great fight nights and get some Fight of the Nights."

Victory FC 54 took place Dec. 9 at the Baxter Arena in Omaha, Nebraska. The event aired live on UFC Fight Pass.

In the night's headlining bout, Kassius Kayne defeated Maki Pitolo via brutal, one-punch knockout at :05 of the second round to claim the vacant Victory FC welterweight title.