Johanna Konta extended her winning streak to 15 matches as she dumped ninth seed Garbine Muguruza out to create a slice of US Open history on Thursday.

In the longest women's match at the grand slam event since tie-breaks were introduced in 1970, British qualifier Konta celebrated a 7-6 (7-4) 6-7 (4-7) 6-2 second-round triumph over this year's beaten Wimbledon finalist. 

Victory at Flushing Meadows - which was sealed in three hours and 23 minutes - also means Konta is through to the third round at the US Open for the first time in career.

Awaiting Konta is German Petkovic, who scored a 6-3 7-6 (7-4) win over Elena Vesnina.

Romanian second Simona Halep continued her run at the US Open with a 6-3 6-4 victory against Kateryna Bondarenko.

Halep - with three singles titles under her belt this year - proved too strong for the Ukrainian in the first meeting between the pair, converting all four break-point chances and tallying 10 fewer unforced errors.

Next up for Halep is Shelby Rogers, who downed Kurumi Nara 6-4 6-4.

For the fourth straight year, Petra Kvitova reached at least the third round at Flushing Meadows after beating Nicole Gibbs 6-3 6-4.

Kvitova, the fifth seed at the year's final grand slam, served well, sending down five aces.

Former world number one and two-time finalist Victoria Azarenka finished strongly as she defeated Yanina Wickmayer 7-5 6-4.

Standing in the way of Azarenka and a fourth-round berth is Angelique Kerber after the 11th-seeded German overcame Karin Knapp 7-5 6-2.

Samantha Stosur - the 2011 champion - only needed 51 minutes to see off Evgeniya Rodina 6-1 6-1.

Stosur's win earned her a showdown with 16th seed Sara Errani, who rallied to beat Jelena Ostapenko 0-6 6-4 6-3.

Sabine Lisicki and Barbora Strycova will go head-to-head in the third round.

Lisicki - seeded 24th - was too good for Camila Giorgi 6-4 6-0, while Strycova prevailed 6-2 4-6 7-5 against Qiang Wang.

Monica Barthel overcame Olga Govortsova 2-6 6-2 6-4 to setup a meeting with Varvara Lepchenko, who edged Lesia Tsurenko 7-6 (9-7) 6-2.

Flavia Pennetta was a 6-1 6-4 winner at the expense of Monica Niculescu.