SYDNEY (AP) — Greece badly missed Stefanos Tsitsipas in the singles when it was beaten by Poland on the opening day of the 16-team ATP Cup tournament on Saturday.

The fourth-ranked Tsitsipas had to withdraw with an elbow problem ahead of his match with ninth-ranked Hubert Hurkacz, who went on to beat replacement Aristotelis Thanos 6-1, 6-2 to give Poland an unassailable 2-0 lead after Kamil Majchrzak had defeated Michail Pervolarakis 6-1, 6-4 earlier.

Tsitsipas watched from the team bench, with ice wrapped around his right elbow, as the 1,076th-ranked Thanos was outclassed by Hurkacz.

Greece then gained some consolation when Tsitsipas combined with Pervolarakis in the doubles to overcome Szymon Walkow and Jan Zielinski 6-4, 5-7, 10-8.

Tsitsipas had an operation in late November, with a flare-up a concern ahead of this month's Australian Open.

“The recovery from my elbow surgery is on track and today was a precautionary step to make sure I make Melbourne,” Tsitsipas said. “We will see day-by-day, match-by-match until then.”

Argentina's Diego Schwartzman and Spain's Roberto Bautista Agut led their respective teams to comfortable victories earlier on Saturday.

Argentina beat Georgia 3-0, while Spain easily accounted for Chile by the same margin at the tournament being played across two Sydney stadiums.

The 13th-ranked Schwartzman defeated Georgia's Nikoloz Basilashvili 6-1, 6-2, after compatriot Federico Delbonis won by the same score against Aleksandre Metreveli to give Argentina a 2-0 lead from the singles matches.

Maximo Gonzalez and Andres Molteni then gave the Argentines a clean sweep defeating Georgian pair Saba Pertseladze and Zura Tkemaladze 6-1, 6-2 in the doubles tie to give Argentina a 3-0 win.

Pablo Carreno Busta gave Spain an early lead as he rallied from being a break down in both sets to defeat Chile's Alejandro Tabilo 6-4, 7-6 (7-4).

Roberto Bautista Agut appeared in excellent form as he disposed of Chile’s Cristian Garin 6-0, 6-3 to seal the tie for Spain.

Alejandro Davidovich Fokina and Pedro Martinez clinched a clean sweep for Spain with a 7-6 (3), 4-6, 10-7 win over Chile's Tomas Barrios Vera and Tabilo.

Even without Rafael Nadal, whose preparation for the Australian Open has been disrupted by a positive test for coronavirus, Spain showed why they are among the favored teams at the tournament.

“Today was a good start for me, a very solid game, really happy. I like these conditions," Bautista Agut said.

Serbia, which is without top-ranked Novak Djokovic, beat Norway 2-1. Filip Krajinovic did double duty — teaming with Nikola Cacic to overcome Casper Ruud and Viktor Durasovic 7-6 (3), 6-3 in the decisive doubles match after the two singles matches were split,

The other eight teams begin play Sunday: Russia vs. France, Italy vs. Australia, Canada vs. the United States and Germany vs. Britain.

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