The 22-year-old Dane got to bed late after outlasting Elina Svitolina in a three-set victory in the previous round.
"I think I slept maybe five hours last night. We went to sleep at 330 am," Clauson, ranked 38th, said in her on-court interview. "I didn't know what shape I was going to come out here in, but a pretty good one."
Tauson, who lost to Sabalenka at the Australian Open, had not previously beaten a No. 1-ranked player.
Next up is Linda Noskova for a shot at the semi-finals. The Czech player beat fifth-seeded Jessica Pegula 6-3 7-6 (10-8).
Sabalenka has lost two of her three matches on the WTA Tour since being beaten in the Melbourne final by Madison Keys.
Second-seeded Iga Swiatek beat Dayana Yastremska 7-5 6-0 and next faces Mirra Andreeva, who overcame Peyton Sterns 6-1 6-1.
Defending champion Jasmine Paolini was ousted by Sofia Kenin 6-4 6-0.
The Italian sustained a right ankle injury during the second set. A tearful Paolini got a medical timeout and had her ankle immobilised, but could not challenge Kenin afterward.
Kenin will face sixth-seeded Elena Rybakina in the quarterfinals. Rybakina beat ninth-seeded Paula Badosa 4-6 7-6 (10-8) 7-6 (7-2).
Elsewhere the WTA Tour banned a man who exhibited "fixated behaviour" towards Emma Raducanu after he was taken away by security personnel during the Briton's match late on Tuesday.
Former US Open champion Raducanu appeared to be in tears as she approached the umpire's chair during the first set of her second-round defeat to Karolina Muchova.
The match was briefly halted after Raducanu spoke with the umpire, who quickly contacted tournament organisers. The 22-year-old stood behind the official's chair as the spectator was escorted away.
The man had previously approached Raducanu at the event on Monday.
The 22-year-old has previously had problems with obsessed fans. In 2022 a man who stalked her in England was handed a five-year restraining order. Amrit Magar had walked 23 miles to Raducanu's home and taken her father's shoe as a souvenir.
with Reuters
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