Daniel Cormier was saddened by Khabib Nurmagomedov's surprising retirement at UFC 254.
The former two-division champion, who's also a longtime teammate of Nurmagomedov at American Kickboxing Academy, said he thought the lightweight titleholder would compete at least once more after submitting Justin Gaethje in the second round Saturday in Abu Dhabi, United Arab Emirates.
"I've met guys like Khabib before in wrestling - Olympic champions that walk away at the very top of the sport when you know they have so much more to give," Cormier said while serving as the color commentator for the event's broadcast.
"And if he says it, I'm certain that we won't see Khabib again, which is heartbreaking. He's such a phenomenal, once-in-a-lifetime talent. You want to see him in there until he's 40-0."
Nurmagomedov said he promised his mother his title defense against Gaethje would be his final fight. His father, Abdulmanap Nurmagomedov, died in July of a heart condition complicated by the coronavirus.
"The Eagle" is walking away from the sport with a 29-0 record and as one of the most dominant fighters in UFC history.