Johanna Konta fought back from the brink of defeat to claim a remarkable victory over top seed Simona Halep at the Wuhan Open on Wednesday.

World number two Halep looked set to secure her place in the quarter-finals in China when she led 5-1 in the final set, but a defiant Konta refused to accept defeat.

Konta was outside the top 100 at the end of the grass-court season, but shock wins over Ekaterina Makarova and Garbine Muguruza have seen the relatively unknown 24-year-old Brit surge up to number 66 in the world.

Halep was the latest player to discover that the in-form Konta is one to watch after she rallied to win 6-3 3-6 7-5 in two hours and 17 minutes to set up a last-eight contest with Venus Williams. 

Qualifier Konta needed just the one break in the first set as she raced into a 3-0 lead and did not allow the favourite a solitary opportunity to break back.

Halep responded with two breaks to Konta's one in the second to level the match and looked certain to complete the comeback as she took complete command of the decider, needing only one game to secure victory at 5-1.

Konta came through two qualifying rounds to reach the last 16, but was clearly not hampered by fatigue as she battled back to claim a major scalp.

Petra Kvitova also suffered a third-round defeat as US Open runner-up Roberta Vinci triumphed 7-6 (7-3) 6-2 against the third seed.

Williams accounted for seventh seed Carla Suarez Navarro 6-3 6-4 and will now turn her attention to bringing Konta back down to earth.

Wimbledon finalist Muguruza, seeded five, fought back in emphatic fashion to beat Ana Ivanovic 4-6 6-1 6-0

Karolina Pliskova and Anna Karolina Schmiedlova were also third-round winners on Wednesday.