INDIAN WELLS: World number one Naomi Osaka crashed out of Indian Wells on Tuesday, routed by Belinda Bencic on a day that saw second-ranked Simona Halep sent packing, too.
Bencic, ranked 23rd in the world, defeated Osaka 6-3, 6-1 to reach the quarter-finals of the prestigious WTA premier mandatory event, where Osaka won her first tour title last year.
That marked the start of a remarkable rise that included Osaka's first Grand Slam title at the US Open. She followed that with an Australian Open crown that sent her to number one.
But she never found her feet against Bencic, whose crisp groundstrokes and precise service game propelled her to victory in 66 minutes.
"I didn't play that well," Osaka said. "Honestly, at a time like this with that scoreline, I would usually feel very depressed and sad. But I feel pretty good right now, because I tried my best and I don't really have any regrets.
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"She was just playing so well ... there wasn't anything that I could do in that situation."
Bencic, who turned 22 on Sunday, is back on the rise after a string of injuries stalled a career that had exploded with two precocious WTA titles in 2015.
Bencic -- who beat four top-10 players on the way to the title in Dubai last month, her first trophy in four years -- next faces fifth-seeded Czech Karolina Pliskova, who downed Anett Kontaveit 7-6 (10/8), 4-6, 6-2.
The victory over Osaka came in "very high" in her list of big wins.
"I mean, she's the number one player in the world. She won everything in the past couple of months.
"I played, I think, a great match. I'm really happy with myself.
"I'm very confident with my game right now. I'm hitting the ball well. So just things worked out for me."
Osaka's defeat capped a black day for top seeds in the combined WTA-ATP Masters event, with men's world number one Novak Djokovic stunned by 39th-ranked Philipp Kohlschreiber.
The women's field lost its top two seeds as Romania's Halep, the 2015 Indian Wells winner, fell to Czech teenager Marketa Vondrousova 6-2, 3-6, 6-2.
Halep, who received treatment for blisters on her foot during the match, hit just six winners and piled up 36 unforced errors.
"I was running too much and too defensive," she said. "But it's everything I could do today."
Osaka keeps Indian Wells title defense on track
Her defeat means Osaka will retain her number one ranking, even though she couldn't pull off her first title defense.
Vondrousova, who beat 2018 runner-up Daria Kasatkina and former French Open winner Jelena Ostapenko on the way to the fourth round, will go for another big win when she faces sixth-seeded Elina Svitolina, who battled to a 7-6 (10/8), 5-7, 6-4 victory over Australian Ashleigh Barty.
Former world number ones Venus Williams and Garbine Muguruza made it into the quarter-finals.
Spain's Muguruza, a two-time Grand Slam champion now ranked 20th in the world, out-lasted seventh-ranked Kiki Bertens 5-7, 6-1, 6-4 while Williams, a seven-time Grand Slam winner, beat Germany's Mona Barthel 6-4, 6-4.
Muguruza next faces 18-year-old Canadian Bianca Andreescu, who surprised China's 18th-seeded Wang Qiang 7-5, 6-2.
Andreescu -- who roared to her first WTA final as a qualifier in Auckland in January, beating two former world number ones on the way -- is in the quarter-finals of one of the WTA's elite premier mandatory events for the first time.
Andreescu improved her match record for 2019 to 25-3, including qualifying, as she became the youngest player to make the last eight at Indian Wells since a 17-year-old Anastasia Pavlyuchenkova reached the semis in 2009.
Williams will fight for a semi-final berth against eighth-seeded Angelique Kerber, who beat ninth-seeded Aryna Sabalenka of Belarus 6-1, 4-6, 6-4.