Ekaterina Makarova stuns French Open champ Jelena Ostapenko in Sydney first round
Ekaterina Makarova is off to a strong start in Sydney. AP

SYDNEY — French Open champion Jelena Ostapenko had an upset 7-6 (3), 6-1 loss to Ekaterina Makarova on a sweltering opening day of the Sydney International.

No. 3 Ostapenko was one of two highly-seeded players to exit the women's draw in the first round, with fifth-seeded Kristina Mladenovic retiring earlier on Sunday from her earlier match while trailing Australian wildcard entry Ellen Perez, 6-4, 4-2.

Julia Gorges also withdrew from the tournament Sunday after winning the ASB Classic final against Caroline Wozniacki in Auckland, New Zealand.

The conditions forced organizers to activate heat policies — including longer breaks between sets — during part of the day, with some areas of western Sydney experiencing the hottest day in almost 80 years with temperatures peaking above 47 Celsius (117 Fahrenheit).

In men's first-round matches, Alexandr Dolgopolov edged Viktor Troicki 6-3, 6-7 (6), 7-5, Damir Dzumhur beat Jan-Lennard Struff 6-1, 6-4 and Paolo Lorenzi had a 7-6 (5), 6-4 win over Jordan Thompson.

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