NEWPORT BEACH, CA, USA -- Former Top 10 player CoCo Vandeweghe and resurgent Alexa Glatch were two of the six American winners on Monday in the first round of the Oracle Challenger Series Newport Beach, the first WTA 125K Series event of the 2020 season.

Vandeweghe shook off a first-round loss to Laura Siegemund at the Australian Open to claim her first main-draw victory of the year over Colombian teenager Maria Camila Osorio Serrano, 6-4, 6-1.

The former World No.9 and two-time Grand Slam semifinalist broke Osorio Serrano five times in the encounter while also saving five of the six break points she faced in the clash. The second set went entirely Vandeweghe’s way, as she won 83 percent of points on her first serve while triumphing on all ten of the Colombian’s second-service points during that timeframe.

Vandeweghe moves on to set up a second-round tilt against her fellow American, 10th-seeded Allie Kiick. The 16 seeded players all received first-round byes.

Glatch, who missed all of 2018 and part of 2019 due to injuries, is back in the Top 300 of the WTA singles rankings, after nearly cracking the Top 100 over ten years ago.

She also had a quick day at the office, dispatching former World No.5 and 2014 Wimbledon finalist Eugenie Bouchard of Canada, 6-1, 6-2, in just 64 minutes. Glatch won three-quarters of points on her first serve, and a nearly equivalent amount of points off of the Bouchard second serve.

After an early exchange of breaks to start the match, Glatch crushed a return winner to break Bouchard for a 3-1 lead, and refused to rescind that advantage from there. On her first set point at 5-1, Glatch blasted a big serve to force a netted return, claiming her fourth straight game and a one-set lead.

In the second set, Glatch eased to 5-2, where she claimed her first match point with a stirring backhand winner down the line. A Bouchard backhand flew long on the next point, ceding the win to the American. Glatch will also have an all-American affair in the second round, when she takes on No.13 seed Shelby Rogers.

Winners in Monday’s all-American first-rounders include Claire Liu, who beat Jamie Loeb 6-4, 6-2, Grace Min, who ousted Katie Volynets, 6-3, 7-5, and Hailey Baptiste, who overcame Kayla Day, 4-6, 6-4, 6-3. Sophia Whittle was the sixth American winner of the day, as she beat Kazakhstan’s Anna Danilina, 6-2, 6-2.

Former World No.5 and 2012 Roland Garros finalist Sara Errani of Italy was another victor, taking out Mexico’s Marcela Zacarias, 6-1, 6-2, to set up a second-round match against No.1 seed Jessica Pegula. But Mexico also had a winner, as Ana Sofia Sanchez beat Serbia’s Jovana Jovic, 6-4, 5-7, 6-4 after nearly three hours of play.

Two Frenchwomen also picked up straight-set wins, as Amandine Hesse beat Catherine Harrison of the United States, 6-4, 7-5, and Jessika Ponchet eliminated Latvia’s Diana Marcinkevica, 6-3, 6-2.

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