Jairzinho Rozenstruik is back in the win column.
The heavyweight contender defeated Augusto Sakai via TKO at the 4:59 mark of the first round in the UFC Fight Night main event Saturday at the UFC Apex in Las Vegas.
Rozenstruik's right punch to the temple dropped Sakai with four seconds left in the round. He followed up with a few heavy shots on the ground until referee Herb Dean waved off the contest.
"We've been working hard, and this is what we wanted," Rozenstruik said in his postfight interview.
The No. 6-ranked contender sent a message to the top-five heavyweights after the victory.
"I'm coming for you guys," Rozenstruik said. "I'm coming."
The 33-year-old returned to the winner's circle after falling short against Ciryl Gane in a headlining bout earlier in 2021. He earned his eighth career knockout and 12th professional victory against Sakai, improving his record to 12-2.
Rozenstruik has alternated wins and losses over his past four matchups, as he finished former champion Junior dos Santos last summer after suffering a knockout loss to current titleholder Francis Ngannou.
Sakai, the No. 9-ranked heavyweight, is now riding the first two-fight skid of his career. The 30-year-old is 4-2 in the Octagon and 15-3-1 as a professional.