(Photo credit: Eric Bolte-Imagn Images)

Tallon Griekspoor saved four match points in upsetting top seed Daniil Medvedev 2-6, 7-6 (7), 7-5 in the quarterfinals at the Dubai Tennis Championships on Thursday.

The Dutchman advanced to his eighth career ATP Tour semifinal (3-4 record) in knocking off Russia's Medvedev, the 2023 winner of this event who posted 15 aces on this day. Griekspoor saved 11 of 14 break points while converting 2 of 7.

Griekspoor next faces fourth-seeded Stefanos Tsitsipas of Greece, a 7-6 (5), 1-6, 6-4 winner over Italy's Matteo Berrettini. Canada's Felix Auger-Aliassime defeated Croatia's Marin Cilic 6-4, 3-6, 6-2 to advance to the semifinals against French qualifier Quentin Halys, who also went three sets to hold off Italian lucky loser Luca Nardi 2-6, 6-3, 7-6 (5).

Movistar Chile Open

Argentina's Federico Coria saved four set points in the first-set tiebreaker and emerged with a 7-6 (11), 4-6, 6-3 win over second-seeded Alejandro Tabilo of Chile in the second round at Santiago, Chile.

Coria needed four set points before he captured the tiebreaker, then prevailed in a match that lasted 2 hours, 37 minutes, to earn a spot in the quarterfinals.

Third-seeded Sebastian Baez eked out a 6-3, 5-7, 7-6 (5) victory over Argentine countryman Francisco Comesana. Another Argentine, Camilo Ugo Carabelli, advanced by rallying past Brazil's Thiago Monteiro 4-6, 7-6 (2), 6-3, but Bosnia's Damir Dzumhur downed sixth-seeded Mariano Navone of Argentina 6-4, 3-6, 6-3.

Abierto Mexicano Telcel

U.S. qualifier Learner Tien couldn't make it two upsets in a row, falling 6-3, 7-5 to eighth-seeded Tomas Machac of the Czech Republic in the quarterfinals at Acapulco, Mexico.

A day after Tien ousted top-seeded Alexander Zverev of Germany, the American lost his serve six times and won just 54.9 percent of his first-serve points.

Machac's semifinal opponent will the United States' Brandon Nakashima, who topped Belgium's David Goffin 7-6 (4), 6-2.

The last two semifinal berths were set to be decided later Thursday night. Ninth-seeded Denis Shapovalov of Canada was ready to oppose the United States' Marcos Giron, and Spain's Alejandro Davidovich Fokina was prepared to face 19-year-old Mexican Rodrigo Pacheco Mendez.

--Field Level Media