The German second seed had gone to bed the previous evening tantalisingly close to breaking new ground at Wimbledon, leading by two sets and 3-3 in the third when Wimbledon's strict 11 p.m. curfew halted his progress.
On the resumption, a listless-looking Zverev lost 12 of the first 13 points to drop the third set but managed to re-focus to win 6-4, 7-5, 3-6, 7-6(6).
Zverev double-faulted on a second match point in the tiebreaker but was spared further overtime as 13th seed Lehecka netted a backhand.
His attempt to add the Wimbledon crown to his maiden Grand Slam title at last month's French Open will continue with a heavy-metal last-eight clash with American Taylor Fritz.
FIFA World Cup 2026
The 2026 World Cup is taking place from June 11th to July 19th in the United States, Canada and Mexico. The tournament features 48 national teams and is played at 16 modern stadiums.
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