The fiery Australian produced another extraordinary performance to demolish compatriot Alex de Minaur 6-2 6-3 at the Canadian Masters on Thursday.
His victory came just a day after stunning world number one Daniil Medvedev.
The Wimbledon finalist has been playing the best tennis of his career and is showing no signs of slowing down in Montreal, where he won the first four games of the opening set in which de Minaur won scarcely more than half of his first-serve points.
Kyrgios briefly appeared agitated when he gave up a break in the penultimate game but found his composure to get the job done in a little over an hour, breaking back to love in the final game.
The win will move Kyrgios high enough in the rankings to be seeded at the U.S. Open later this month.
"I did what had to be done. He's a hell of a player if you play to his strengths, he's one of the best players from the back in the game, he's just so fast," Kyrgios said of de Minaur in on-court remarks after the match.
Kyrgios has won 15 of his last 16 matches and a day earlier produced a serve-and-volley masterclass to stun Medvedev 6-7(2) 6-4 6-2. He said the effort had certainly taken a toll.
"Incredibly tough, after yesterday's big high-playing Daniil. The crowd was amazing, it's a day I'll probably never ever forget," he said.
"Today was really hard for me mentally to play Alex, we're such good friends and he's been having such a good career so far carrying the Australian flag. It's just tough mentally, it's never easy to play a friend like that, especially if they're an Australian."
Kyrgios next faces Poland's Hubert Hurkacz in the quarter-final round.