Cain Velasquez’s highly anticipated return was at least partially spoiled by his infamous nemesis: the injury bug.

After a 30-plus month layoff from competition, Velasquez’s comeback fight in the main event of UFC Phoenix on Sunday opposite Francis Ngannou lasted just 26 seconds. The end came when Velasquez attempted to grapple with Ngannou and the towering Frenchman responded with a few fiery punches in close. Velasquez dropped to the mat, then rolled over onto his front, seemingly unable to defend himself as referee Jason Herzog stepped in to call the bout.

Velasquez let out a roar of frustration immediately following the stoppage and the replays seemed to indicate that his left knee gave out on him. He confirmed as much at the evening’s post-fight presser, explaining exactly when the injury happened and how devastating the outcome was to him.

“I just can’t believe that happened,” Velasquez said. “Having a great camp coming in, truly, everything I said, how strongly I felt, that was all true. Coming in I felt great out there, relaxed, and then taking that one step I did with my left foot. I just felt something pop and then when I tried to take another step it just gave out on me. My knee gave out on me, I can’t even believe that happened.

“Going in 100 percent healthy. 100 percent ready and just to have this freak accident, I can’t even believe it. It’s just hard. That’s sports, that’s what we do. That’s what happens sometimes. It’s just really frustrating because the fire in me is strong, stronger than ever. In camp, great camp, great camp. And then this happens.”

Velasquez speculated that the injury could have occurred to his meniscus or MCL, though further examination will be required. He felt a pop in his left leg as he advanced and then when he tried to move left again, that’s when it completely gave out. Making matters worse for Velasquez is that as far as he knows, there were no previous issues with his left knee.

Upon further examination of the finish, it looks like at least one of Ngannou’s counter-punches landed cleanly and Velasquez was asked how much the power of Ngannou contributed to the finish and how much of it was due to his injury.

“It was just the knee, he didn’t even, like, touch me, you know?” Velasquez said. “It was just the knee, as soon as I felt the knee just buckle, it was like I couldn’t believe that happened. And then that was it.”

“Going in for his leg, I felt he kind of clubbed me on the back of the head, but that didn’t graze me at all,” Velasquez continued. “None of the punches grazed me at all or did anything to myself where I felt like I was unbalanced or anything. Just getting in on the inside and it was just a freak thing that happened with my knee.”

Velasquez didn’t fault Ngannou for going in for the kill, nor Herzog for the fast stoppage. If anything, it sounded like he was most disappointed in his body betraying him once more.

“It was okay because the ref saw my knee buckle.” Velasquez said. “The ref saw my knee buckle. His job is to make sure we’re 100 percent safe and he did that. Even for me, just to process what happened in that moment, even afterwards — the ref did the right job, he did the correct job tonight.”

“I have a lot of respect for [Ngannou] — I have a lot of respect for a lot of fighters, that’s just how I am — Before the fight, a lot of respect, but I’m there to kill him,” Velasquez continued. “After the fight, a lot of respect, especially for him as a man, as a competitor.

“I beat myself tonight.”

Velasquez could not speak on the severity of the injury nor provide a potential timetable for his next bout. When asked if this could be his last fight, Velasquez simply said that he’ll only stop when he feels like he “can’t be the best” and that that wasn’t “the case with this whole camp.” The 36-year-old already has two UFC heavyweight reigns on his resume, though he now has just one win in his last three fights dating back to June 2015.

The keyword for Velasquez in describing Sunday’s fight was “frustrating”, because other than how it all ended, Velasquez felt right at home back in the Octagon.

“We’ll see what happens going forward,” Velasquez said. “Again, knowing what I did these past three years and two months, getting ready for this camp, I felt ready. Extremely ready. I felt calm out there, like the Octagon was the place I needed to be and I felt great. It felt great coming back. It felt great in there with him.

“And then the freak accident with the knee just popping out. It’s just frustrating, but we’ll get it all checked out. The fire in me is strong again still and I guess I’ve got a lot to prove and I’m very capable of doing that.”