Britain's Harriet Dart battled through to Round 2 at the US Open after coming from a set down to oust home hope Peyton Stearns.
The 30-year-old, who had to come from behind to beat compatriot Heather Watson in the final round of qualifying, won a grueling tussle 3-6 6-3 6-2 in two hours and 24 minutes.
Dart needed treatment on a foot problem after winning the second set and squandered three match points in a nervy ending.
But she got over the line with a fourth, clenching her fists in delight when Stearns netted a forehand before celebrating with former Wimbledon champion Marion Bartoli, who is part of her coaching team.
Frenchwoman Bartoli won the SW19 title in 2013 and has been working with Dart on an ad-hoc basis since January.
"She does a lot of my training weeks as we live near each other," Dart said.
"She's done primarily the Slams, but on the grass she did three weeks, and before here in Florida. She has a busy schedule and so do I so we have to coordinate but I feel like I'm benefiting from all the work we do together.
"She a great coach and an even better person -- she's very funny -- but I'm just trying to soak up as much as I can from such a champion."
British No. 1 Katie Boulter, who beat American wild card Carol Young Suh Lee on Sunday, found out her next opponent will be seventh seed Karolina Muchova after the Wimbledon runner-up thrashed Sinja Kraus 6-3, 6-0.
Fearnley wins marathon against Landaluce
In the men's draw, Jacob Fearnley picked the worst possible moment to play probably the worst shot of his entire career.
The British No. 4, only in the first round proper as a lucky loser, was on match point and had the simplest of overhead putaways to secure a five-set victory over Spain's Martin Landaluce.
But Fearnley must have taken his eye off the ball as he missed it completely, playing an air shot any club player would have been embarrassed by, before scrambling back to keep it in play.
Landaluce went on to win the point, and to rub salt in the wounds even the ball kid was smirking as Fearnley trudged back to the service line.
Having been leading 5-1 in the final set, shell-shocked Fearnley was reeled back to 5-3, but he held his nerve to eventually serve out for a 4-6, 6-2, 4-6, 7-5, 6-3 victory, at four hours and 10 minutes the longest match of his career.
