But Tsitsipas’ 71st-ranked rival – who will move inside the world’s top 40 next week – had fistfuls of chances, failing to convert five break points in the fourth game of the second set, then three more from 0-40 in the seventh game of the next set.
Neither moment killed Lehecka’s resistance, but not capitalising cruelled his hopes of joining Ivan Lendl, Tomas Berdych, Petr Korda and Jiri Novak as the only Czech men to reach a semi-final at Melbourne Park.
After not facing a break point since dropping serve at the start of the match, Lehecka eventually wilted when he dumped a backhand into the net on Tsitsipas’ first match point.
Either Tsitsipas or Russia’s Karen Khachanov – who progressed to consecutive grand slam semi-finals at American Sebastian Korda’s expense earlier on Tuesday – will play in their first Australian Open final on Sunday night.
Khachanov has never beaten Tsitsipas in five meetings, with their most recent clash in Rome on clay last year.
“It’s a match that I’m looking forward to. It’s great to be back in the semi-finals,” Tsitsipas said.
“Of course, I’m definitely happy with the way I’ve been playing so far. I’m looking ahead for more, for better. I’m looking to create some magical experiences here in Australia.”
Tsitsipas remains perfect in six career grand slam quarter-finals, but his sole final from those opportunities was at the 2021 French Open, where he agonisingly lost from two sets up against Novak Djokovic.
The desperation from all quarters for someone, anyone, to dethrone the “Big Three” of Djokovic, Rafael Nadal and (while he was still playing) Roger Federer means patience runs too thin at times.
Former “Next Gen” members Tsitsipas, Alex Zverev, Daniil Medvedev, Casper Ruud and Andrey Rublev have all enjoyed plenty of success, but only Medvedev owns a grand slam title from that group.
The new world No.1 Carlos Alcaraz is only 19 and has one already, while the likes of Holger Rune and Jannik Sinner are also rising fast, so harsh labels such as “Lost Gen” have started being thrown around.
But Tsitsipas eliminated Sinner from the Open for the second straight year two nights ago – although he needed four hours and five sets this time – and has now put a stop to 21-year-old Lehecka’s brilliant run, which included upsetting Borna Coric, Cameron Norrie and Felix Auger-Aliassime.
Tsitsipas played down the significance of whom he had beaten, saying he did not put “labels” on his opponents, but the message with his emphatic play was simple.
They might be coming but Tsitsipas is part of Generation Now, or whatever you want to call it, and has a huge opportunity in front of him in the coming days.
“I’m feeling great with my tennis. I don’t think I’ve felt so good in a long time,” he said.
“I’m a different player, playing different. My mentality is different. When I’m out on the court; I don’t really think of negatives, to be honest. I just go out there and play the game.
“I’m very happy to be out on the court. I’m very happy to be performing. I’m very happy to hit some good shots, come in. It’s just this whole dynamic that has made me very hungry and created a lot of desire for me to be playing tennis, wanting to achieve new things.”
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