Ryan Garcia admitted he "just couldn’t get up" from the body shot Gervonta ‘Tank’ Davis used to clinch victory in Las Vegas.
The fight, shown live on DAZN around the world, ended in a seventh-round knockout victory for Tank as he took his younger challenger’s undefeated record.
Garcia suffered an earlier knockdown but was able to recover the first time, but when he attempted to land a hook of his own, the shorter man was alive to the threat and delivered a blow to the liver.
It took a couple of seconds to register on Garcia but he had to take a knee and was counted out as he struggled to get back to his feet.
However, he could not manage it and the referee called off the fight in Tank’s favour.
Speaking after the fight, Garcia acknowledged that there was too much power in the blow for him to recover.
"I just couldn't recover. Snuck under me and caught me good," Garcia said.
"I was going to get back up, but I just couldn't get up."