Greece's Stefanos Tsitsipas hits a return to US player Frances Tiafoe during their men's singles first round match on the first day of the 2021 Wimbledon Championships at The All England Tennis Club in Wimbledon, southwest London, on June 28, 2021. (BEN STANSALL / AFP)

Top seed Stefanos Tsitsipas of Greece needed a first-set tiebreak but then handled business against Germany's Dominik Koepfer, winning 7-6 (2), 6-3 on Wednesday at the Hamburg European Open in Germany.

Stefanos Tsitsipas advanced to the quarterfinals to face Serbian Filip Krajinovic

It marked Tsitsipas' first match since being upset in the first round at Wimbledon by American Frances Tiafoe. He won 86 percent (30 of 35) of his first-serve points en route to securing his tour-best 40th win of the season.

Tsitsipas advanced to the quarterfinals to face Serbian No 6 seed Filip Krajinovic, who outlasted German wild card Philipp Kohlschreiber 7-5, 4-6, 6-3 on Wednesday. Fellow Serbian Laslo Djere also notched another win, defeating Brazil's Thiago Seyboth Wild 7-6 (1), 6-1.

Hall of Fame Open

American No 2 seed Sam Querrey fell to countryman Maxime Cressy on Wednesday, one of four seeded players to bow out in Newport, RI.

Cressy won 6-4, 2-6, 6-2 in the pair's first career head-to-head match. He is joined in the quarterfinals by two other Americans: Jenson Brooksby, who defeated fellow American Denis Kudla, and Jack Sock, who upset No 3 seed Yoshihito Nishioka 6-2, 6-3.

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German Peter Gojowczyk knocked out Canadian No 4 seed Vasek Pospisil 6-3, 6-3, and Jason Jung of Chinese Taipei beat American No 5 seed Tennys Sandgren 6-2, 6-2.

No 1 seed Alexander Bublik of Kazakhstan needed three sets to avoid following his fellow seeded players out the door. He beat Croatia's Ivo Karlovic 7-6 (5), 4-6, 6-1. No 7 seed Jordan Thompson of Australia and No 8 seed Kevin Anderson of South Africa also advanced.

Nordea Open

No 2 seed Cristian Garin converted four of six break points and won 75 percent of his first-serve points on the way to defeating Spain's Pedro Martinez 6-3, 6-3 Wednesday in Bastad, Sweden.

The Chilean Garin made it to the quarterfinals, where he'll meet another South American, Federico Coria of Argentina. Coria rallied for a 4-6, 6-4, 6-3 win over Italy's Marco Cecchinato.

Two seeded players lost in Bastad. Fourth-seeded John Millman of Australia lost to Frenchman Arthur Rinderknech 6-3, 3-6, 6-3. Germany's Yannick Hanfmann eliminated No 7 Jiri Vesely of Czech Republic 6-4, 6-3.