Pegula was the aggressor from the outset, with Svitolina unusually passive, allowing the American to dictate the early proceedings, clinching the first set.
Ukrainian Svitolina rallied in the second set and helped by a patchy spell from Pegula leveled the match. But Pegula recovered her poise and ran away in the final set to reach the last eight of a grand slam for the first time in her career.
“I’m just happy that I’m competing well, hitting well, moving well. I feel good, everything feels pretty solid, so I’m just going to take that to the next match.”
In beating Svitolina, the 26-year-old recorded her first career top-10 victory. At this year’s grand slam, Pegula has already beaten two-time Australian Open champion Victoria Azarenka, US Open champion Sam Stosur and Kristina Mladenovic without dropping a set.
For the 26-year-old Svitolina, it was her sixth grand slam loss to a player ranked outside the top 30 since she became a top-10 mainstay herself in May 2017 as she searches for her maiden grand slam title.
“It’s disappointing because I’ve been playing very good but I feel like it was one of those days where nothing was going my way.”
Pegula’s victory sets up a meeting with her compatriot and No. 22 Jennifer Brady, who overcame No. 28 seed Donna Vekic 6-1, 7-5 on Monday.