Hurkacz served for match points three times in the second-set tiebreaker, but Lehecka extended the match each time before earning the 11-9 tiebreaker victory. The tables were turned in the second set, when Hurkacz saved match point in the 10th game and three more in the tiebreaker before posting his own 11-9 win.
Russian second seed Andrey Rublev had an easier go of it against Belgian qualifier Zizou Bergs, prevailing 7-5, 6-3. No. 5 seed Alex de Minaur of Australia beat Sebastian Korda 6-4, 6-3, and No. 8 seed Alexander Bublik of Kazakhstan defeated Croatia's Borna Coric 6-3, 6-4.
Hungarian Marton Fucsovics, Kazakhstan's Alexander Shevchenko and Germany's Jan-Lennard Struff also advanced.
IEB+ Argentina Open
Colombian qualifier Daniel Elahi Galan rallied past Argentine wild card Diego Schwartzman 2-6, 6-1, 6-4 in first-round action in Buenos Aires.
Galan saved six of nine break points while converting four of his six break-point opportunities against the former World No. 8.
Argentina's Federico Coria pleased the home crowd with a 7-5, 4-6, 7-5 victory over Austria's Sebastian Ofner. Other winners included Argentine Camilo Ugo Carabelli, Chile's Alejandro Tabilo and Italians Luciano Darderi and Andre Vavassori. Two matches were still in action to conclude the night's schedule.
Delray Beach Open
Australia's Jordan Thompson fired 10 aces compared to his opponent's one en route to upsetting No. 7 seed Daniel Evans of Great Britain 7-5, 6-0, in the first round in Florida.
The eighth seed also bowed out early, as qualifier Zachary Svajda saved seven of eight break points and beat Australia's Max Purcell 7-5, 6-3.
Italian lucky loser Flavio Cobolli rallied past Japan's Taro Daniel 1-6, 6-2, 7-6 (1). Qualifier Nicolas Moreno De Alboran and Australia's Rinky Hijikata also advanced, while three more matches were still to come in the nightcap.
