The Canadian eighth seed called upon his huge serve to thump down 39 aces, conceding only one break against the 19-year-old upstart who had rocked the All England Club with the previous day's triumph over world No.1 Rafael Nadal.
Both Kyrgios and Raonic, 23, were playing the day after their fourth-round matches, but the Australian's exertions to claim his momentous win appeared to have taken a physical and emotional toll on the youngest player in the men's draw.
Raonic, who reached the last eight at the French Open last month, is the first Canadian to reach the men's semi-finals of a grand slam in the professional era and now faces seven-times champion Roger Federer on Friday for a place in the final.
The 19-year-old who survived nine match points against Richard Gasquet in the third round, then sent world number one Nadal spinning out of the tournament on Tuesday, finally met his match in Milos Raonic on Wednesday.
While missing out on a semi-final date with seven-times Wimbledon champion Roger Federer must hurt, Kyrgios could draw some inspiration from his hero's path to greatness.
Thirteen years ago a pony-tailed Federer burst onto the big stage when he ended Pete Sampras's charge towards an eighth All England Club title in a five-set thriller in the fourth round.
One round later, the then 19-year-old Swiss had nothing left to give and went out with a whimper.
It took two more years for Federer to finally crack the grand slam riddle but from then on, he has had no equal.
Unlike Federer, who was seeded 15th at the 2001 championships, Kyrgios has turned the tennis world on its head while ranked 144th.
"It's been the best couple of weeks of my life. Never did I think that I was ever going to make quarter-finals of Wimbledon and beat Nadal on Centre Court. It's all happened pretty fast," said the Australian wildcard.
"I woke up this morning and it had sunk in. It was such a great achievement.
"That's something that no one can take away from me. I'm always going to have that now.
"It's been a special week for me. At the same time, it's been so exhausting. I got nothing left to give."
The teenager who spent the first week of the championships easily blending in with the thousands of fans milling around the vast grounds of the All England Club, found himself turning heads when he rocked up for his quarter-final with Raonic.
But the golden arm that fired 37 aces against Nadal on Tuesday, had, unsurprisingly, turned into dead wood 24 hours later.
It was not just Kyrgios who was disappointed with the unhappy ending to his remarkable Wimbledon adventure.
"Clearly I'd like to play against him, too," the 32-year-old Federer said.
"He came to Switzerland to practice with me the week before Rome (in May). We had a great time together. Had good intensity. I already thought he was playing unbelievably at the Australian Open.
"It was nice to see how he works and how he plays in the practice. He's going to rise up the rankings. It would've been cool playing here in the semis with the ranking he has. It's an amazing story."
Walking into uncharted territory, Raonic could be forgiven for fearing 17-times grand slam winner Federer, but he remained defiant at the prospect of facing the Swiss veteran.
"I'm not playing the seven-times Wimbledon champion," Raonic told reporters. "I'm not playing a 32-year-old man. I'm not playing a father of two sets of twins. I'm not playing the guy that's won whatever he's won.
"I'm playing a guy that is standing in the way of what I want to achieve, and I've got to focus on everything that's there, on the situation, how best to deal with it to give myself the best possibilities to achieve what I want."
Raonic, who reached the quarter-finals at the French Open last month, is one of two players outside the world's top four to form the final quartet at the All England Club.
He and 11th seed Grigor Dimitrov, who beat defending champion Andy Murray in straight sets on Wednesday to set up a showdown with 2011 champion Novak Djokovic, are part of a crop of young players tipped to break the so-called Big Four's domination in the grand slams.
"We've been doing better and better, especially throughout this year," Raonic said of the young guns aiming to shoot down the experienced campaigners who, for all their success over the past decade, are beginning to show signs of vulnerability.
"It's nice to see that sort of human side to those four guys when you have to step up to face them and have a belief, more so than ever, that it's yours for the taking if you play well," Raonic said.
"You see it more in people's play and people's attitude when they step out on court. It's a big difference to where a lot of guys were maybe a year ago."
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- Roger Federer
- All England Club
- Rafael Nadal