No.9 seed Marketa Vondrousova picked up another win in her splendid summer, dispatching No.22 seed Ekaterina Alexandrova 6-2, 6-1 on Saturday to reach the Round of 16 at the US Open.

Seven weeks removed from winning her first Grand Slam title at 2023 Wimbledon, Vondrousova needed only 56 minutes to prevail in the late-night clash on Louis Armstrong Stadium, claiming the last remaining spot in this year’s fourth-round lineup.

US Open 2023: Draw | Order of play | Scores | 411

"It's actually my first night session here, and I really enjoyed it," Vondrousova said on court, after her win.

"I'm very happy with my game," Vondrousova continued. "I'm just really grateful to be here playing healthy again, and I'm just enjoying my time here in New York."

With the win, Vondrousova matches her career-best showing at the US Open -- a run to the Round of 16 as a 19-year-old in 2018. The Czech now holds a commanding 4-1 head-to-head lead over Alexandrova, including both of their meetings this year.

Vondrousova has lost a mere 10 games in her three matches this week, as she extends her match-winning streak at Grand Slam events to ten straight victories.

In the Round of 16, Vondrousova will face American Peyton Stearns, which should bring back 2023 Wimbledon memories for both of them. In their lone prior meeting, Vondrousova beat Stearns in the opening round of the Czech's title run in London.

World No.59 Stearns booked a spot in the Round of 16 of a major for the first time with a 6-4, 6-3 victory over Great Britain's Katie Boulter, ranked two spots lower at No.61. Stearns is playing in just her fourth career Grand Slam main draw.

"I don't think I've wrapped my mind around the fact where I am right now because I'm honestly trying not to think about it too much," Stearns told the press afterwards. "I think that's been the biggest key to the success this week, is not letting all of this get to my head."

Stearns needed 1 hour and 37 minutes to best Boulter, who won her first WTA singles title earlier this year in Nottingham. This was much shorter than their previous meeting -- a 3-hour and 22-minute marathon in Austin this year, which Stearns won 7-6(5), 6-7(2), 7-6(5).

Photos: Marathon Marvels 2023: All this year's three-hour matches

Last year's NCAA singles champion Stearns started this year outside the Top 200, but the 21-year-old is already on the verge of cracking the Top 50. Stearns has exhibited that level of form this week -- she hasn't lost more than four games in a set in her three wins.

On Saturday, Boulter charged back from 4-1 down to 4-4 in the opening frame, but Stearns broke the Brit once more to close out the set. In the second set, Stearns eased to a 5-3 lead, but the American had to erase three break points in the final game before she converted her third match point with a forehand winner.