Jiri Lehecka's Grand Slam promise will never be underestimated again.
Three seeded victims en route to his maiden Grand Slam quarterfinal at Melbourne Park have already tipped their hats to the 21-year-old.
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The Czech completely outplayed sixth seed Felix Auger-Aliassime on Sunday, following upsets of 21st seed Borna Coric and 11th seed Cameron Norrie, and subtly warned further boilovers should not be discounted.
Whether third seed Stefanos Tsitsipas or 15th seed Jannik Sinner lined up next mattered little.
Even before the Greek had stamped his quarterfinal ticket later on Sunday, Lehecka expressed not an ounce of trepidation.
"I received the same question after I beat Norrie, so I think we all saw how it went," he said.
"It's tough for me to say. Both of them are incredibly good players.
"I played Stefanos last year in Rotterdam. I lost in three sets and now, of course, here it's Grand Slam, five-set battle, so anything can happen."
The Margaret Court Arena crowd was abuzz on Sunday after a display of the purest ball-striking from the world No.71.
A smooth mover, proficient at net, with a great serve and equally adept off both wings, Lehecka put on a dazzling show that left his opponent offering nothing but praise.
"I think he has a good head on his shoulders, he seems like calm," Auger-Aliassime said. "Young player, not a lot of years on the tour already.
"To be in those moments and to be cool under pressure, play well the right points, serve well to close the match, it's a good sign of a good player. Yeah, I'm sure for those reasons he will be a good player in the future."
Not even a defeat of a rusty former world No.3 Alexander Zverev at the United Cup leading in piqued too much interest among pundits pencilling in dangerous floaters when the Australian Open draw landed less than a fortnight ago.
A year ago, the Czech qualified for his Grand Slam debut at Melbourne Park but after that semifinal run in Rotterdam, it took a while to get the ball rolling again.
The familiarity of the Challenger tour provided more comforting confines to retreat to as he set about slowly building his ranking in 2022.
"I think that the moment when I broke into top 100 was, of course, one of the most beautiful things," Lehecka said of his Rotterdam result.
"But right after it brought a lot of, you know, new challenges, new experiences.
"It was my first time playing all these big tournaments. It was my first time playing all these big players, great names, practising with them.
"Being part of the tour, for me, that was a lot of new things which I learned, and I was trying to learn (along) the way.
"Of course, with this, some bad results came."
It was not until he made a dash at the Next Gen ATP Finals in Milan at year's end that Lehecka's faith was restored.
While he finished runner-up to Brandon Nakashima in the final, it laid the foundation for a blistering start to the new season.
"I think at the Next Gen (Finals), I finally found my game and I found how to play what I want to play, and how to beat great guys in a big stadium," he said.
"I saw all the media attention over there. It was some kind of a gate to the big tennis. They showed us over there how it looks like when you were a pro player."
Lehecka is already assured of a top-40 debut when he departs Melbourne.
Revenge over Tsitsipas would launch him into the top 30.
The first Czech man to reach the quarterfinals since Tomas Berdych five years ago, Lehecka was proud to follow in the footsteps of his idol.
"I mean for me it was always easy. I grew up in the generation when both Davis Cups for Czech Republic were won," Lehecka said. "For me, when I see my own game, I imagine Tomas Berdych.
"It's something that I'm looking up to and I'm trying to inspire myself with the game and with everything that I'm doing on the court."