Day 3 roundup: The time is Nao

NEW YORK, NY, USA - Coming into the US Open, Japan's Nao Hibino
No matter: the World No.80, a two-time finalist this year in Kuala Lumpur and Nanchang, was still able to retrieve a 3-5 final set deficit to finally score that elusive debut victory to the tune of 6-3, 4-6, 7-5. In a finely balanced match, Hibino's winner count inched just ahead of Bellis's, 25 to 23, while she kept her unforced errors a hair lower, 38 to 44.
Elsewhere, there was a 100% success rate for mothers on court as Evgeniya Rodina and Tatjana Maria
Sticking to the formbook, there were a number of contrasting victories for seeded players. No.20 CoCo Vandeweghe was made to fight for a 2-6, 6-3, 6-4 win over compatriot Alison Riske, the tenth edition of the American duo's nine-year rivalry. No.17 Elena Vesnina also had a countrywoman to quell - and for the second Slam in a row, she ended 18-year-old Anna Blinkova
No.27 Zhang Shuai overcame the challenge of Sabine Lisicki 6-7(4), 6-3, 6-0 in the German's fourth tournament back from injury, and last week's champion in New Haven Daria Gavrilova, the No.25 seed, took exactly an hour to move past Allie Kiick, the qualifier making a heartwarming comeback from skin cancer and multiple knee surgeries, 6-2, 6-1.
Powerhouse @SloaneStephens receives a standing ? as she wins her 2nd match here at the #USOpen. @jpmorgan pic.twitter.com/3v1vpG6OuB
— US Open Tennis (@usopen) August 31, 2017
A handful of seeds fell late in the day. No.11 Dominika Cibulkova, just off a run to the Connecticut Open final in New Haven, lost to one of the hottest players of the summer, Sloane Stephens, by the score of 6-2, 5-7, 6-3. Stephens, who has seen her ranking rise over 800 spots in the last month due to back-to-back semifinals at the Rogers Cup and the Western & Southern Open, now faces another rising player, Ashleigh Barty, in the third round. Barty, of Australia, took out Aliaksandra Sasnovich
Meanwhile, in delayed first round play, No.14 seed Kristina Mladenovic
Competitive second round victories went to No.18 seed Caroline Garcia
Also, two of China's top players lost their second round matches in the evening, as Donna Vekic