MADRID — Naomi Osaka and Garbiñe Muguruza were among leading players to be knocked out of the Madrid Open on a day of upsets.

Spain’s Sara Sorribes Tormo beat Osaka 6-3, 6-1 in the second round Sunday on the Spanish capital’s outdoor clay courts. Four-time Grand Slam winner Osaka enjoyed six aces but had her serve broken five times by Sorribes Tormo, who had already bettered French Open runner-up Anastasia Pavlyuchenkova.

Sorribes Tormo next faces Daria Kasatkina, who fought back to upset fourth-seeded Maria Sakkari 3-6, 6-3, 6-1.

Ukraine’s Anhelina Kalinina brushed aside Muguruza 6-3, 6-0.

Muguruza, the reigning WTA Finals champion, had pain in her right calf but said this wasn’t the reason for her defeat.

“I was surprised with her game. I didn’t know her at all,” Muguruza said. “In those break moments, they didn’t work. I just let it go in [on] a couple of points.”

Bianca Andreescu beat sixth-seeded Danielle Collins 6-1, 6-1 after the American lost her serve six times and had six double-faults.

US Open champion Emma Raducanu beat Marta Kostyuk 6-2, 6-1.