Minutes after defeating Justin Gaethje with a second-round submission in UFC 254, Khabib Nurmagomedov announced that he was retiring (via UFC on Twitter).

Capping what would be an undefeated career, Khabib obtained his 29th victory Saturday afternoon, continuing his reign as the UFC lightweight champion.

Collapsing to the ground in tears following the victory, the match was an emotional one for the Russian fighter, who tragically lost his father to heart complications following his diagnosis of COVID-19. Close personally, Khabib's father had also served as his longtime trainer throughout his career, and had been placed in a medically induced coma three months earlier in Moscow, before succumbing to the virus.

Though he had entered the match a favorite against Gaethje, there was concerns that the former collegiate wrestling standout would present a stylistic challenge to Khabib. Attempting to lead with kicks to the legs in the hope that it would open Nurmagomedov to power punches, Gaethje was overpowered and locked in a triangle choke, as Khabib rolled onto his back and forced the challenger into unconsciousness. The referee did, however, seem to miss Gaethje's attempts to tap-out before being put to sleep, as shown on replay.

Despite entering the match with a solid game plan, Gaethje's inability to lay Khabib low, was once again evidence of the lightweight champ's imperviousness to the array of strategies fighters have thrown against him over the years.

While Khabib's announcement was certainly a shock, it was a decision that was not made in the spur of the moment.

“When the UFC called me about Justin, I talked to my mother. She didn't want me to fight without my father, but I promised this would be my last fight” Khabib said.

For a man who very well may end his career ranked as the best pound-for-pound fighter in the world, Khabib's career will not appear to go on without his father.