Alex Pereira KNOWS Jamahal Hill with a brutal first-round finish, seconds after telling the referee to back off, as the Brazilian defends the light heavyweight title in style at UFC 300.

Alex Pereira knocked out Jamahal Hill in the first round of the main event of UFC 300 on Saturday to defend his UFC light heavyweight title for the first time.

In a historic event where Max Holloway had already produced one of the biggest knockouts in the history of the sport, the main event pairing had a tough act to follow.

Hill entered the main event, returning to action after a basketball injury last summer forced him to vacate the title just months after defeating Pereira’s mentor, Glover Teixeira, at UFC 283.

Meanwhile, Poatan had continued his rapid rise since his transition from kickboxing, joining the select group of UFC two-weight champions by defeating Jiri Prochazka in November in just his 11th fight as a mixed martial artist.

From the opening bell at T-Mobile Arena, Pereira stalked the challenger, advancing without regard for Hill’s attacking power.

The matchup marked just the twelfth fight of Pereira’s extraordinary MMA career since transitioning from kickboxing.

A sensation process between the two fighters ensued as Hill attempted to land kicks on the open side in the southpaw vs. orthodox matchup.

Pereira combined body shots with his patented low kicks to force Hill back toward the Octagon fence before a kick from the American was ruled low by referee Herb Dean, who briefly called a pause in the action.

However, the defending champion immediately ignored the intervention, insisting that he could continue fighting.

Just seconds later, Pereira committed to delivering his devastating left hook for the first time in the fight, with the blow landing perfectly on Hill’s jaw and sending him crashing to the canvas.

The challenger recovered admirably as Pereira followed him to the canvas, but the Brazilian’s attack proved too great and the fight was stopped at 3:14 of the first round.

An early kick from Hill landed on the champion’s belt line, causing referee Herb Dean to call a pause in the action.

But Pereira insisted he wanted to continue, and seconds later he landed his trademark left hook to send Hill to the canvas.

The 36-year-old followed up with a series of ground strikes to secure the fifth KO victory of his UFC career.

After the fight, Pereira detailed his ambition to become the promotion’s first three-weight world champion, adding that he would like to make his heavyweight debut at the UFC’s pay-per-view event in Rio de Janeiro.

Such a move could set up a showdown with current interim heavyweight king Tom Aspinall, a fight that had at one point been rumored to take place at this event.