Fourth seed Simona Halep suffered a shock second-round loss to world number 116 Taylor Townsend at the US Open.

American Townsend, 23, won 2-6 6-3 7-6 (7-4) to reach the third round at Flushing Meadows for the first time.

Wimbledon champion Halep, 27, cruised through the opening set but showed her frustration in the third by hitting her racquet on the ground after a miss.

In a thrilling final set, Halep had a match point before qualifier Townsend won in a dramatic tie-break.

An emotional Townsend said: “This means a lot. It’s been a long journey. I had a match point against Kiki Bertens at Wimbledon and close matches this year and not managed to get over the hump.

“This match gives me so much confidence that I can do it. When I’ve played Halep before I tried to make balls and played not to lose. Today I played to win.

“I said to myself this was an opportunity to go for it. There was nothing to lose.”

In front of a large crowd at Arthur Ashe Stadium, it looked like being a routine win for former world number one Halep.

But Townsend fought back with an attacking serve-volley game that saw her move into the net more than 100 times.

She had missed two match points at 5-4 in the final set, double-faulting on the first opportunity before Halep produced a fine down-the-line forehand winner on the second.

The Romanian also had her own chance to win it, but wasted it when she went long with a forehand as Townsend again ran into the net.

In the tie-break, Townsend was never behind and from 4-4 then won the final three points to book her place in the next round.

She will play another Romanian, Sorana Cirstea, who also came from a set down as she beat Spain’s Aliona Bolsova 3-6 6-4 6-2.

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Dan Evans set up another Grand Slam meeting with Roger Federer by beating French 25th seed Lucas Pouille in the US Open second round.

The British number two, 29, dug deep to overcome an out-of-sorts Pouille in a 6-4 6-3 6-7 (4-7) 6-4 win.

Meanwhile, Johanna Konta made an impressive statement as she swatted aside unseeded Russian Margarita Gasparyan in 54 minutes.

The British number one, 28, hit 24 winners in an emphatic 6-1 6-0 victory.

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Evans, now 58th in the world after being unranked last year, impressively punished Pouille in the opening two sets, then recovered well after losing his way in the third.

Federer, who beat Evans at the Australian Open in January, lies in wait on Friday.

Evans was praised by the Swiss great after the Briton pushed him in a 7-6 (7-5) 7-6 (7-3) 6-3 second-round defeat in Melbourne and has another opportunity to test him further in New York.

Federer, 38, said it was like “playing in the mirror a little bit” and then went on to invite Evans to practise with him in Switzerland before the French Open.

Federer has made slow starts in his opening wins over Indian qualifier Sumit Nagal and Damir Dzumhur, looking a shadow of his usual self in poor first sets.

More to follow.

Serena Williams fought back from a set down to beat American teenager Caty McNally in an entertaining late-night match at the US Open.

Williams, 37, took control midway through the second set to win 5-7 6-3 6-1.

The eighth seed dropped just five points in a one-sided final set.

“I survived tonight. I am not too pleased with the way I played at all, but it’s OK, I’m alive. I’ll do better. I promise,” said Williams.

The 23-time Grand Slam champion will play Czech Karolina Muchova or Taiwan’s Hsieh Su-wei in the third round.

Williams thrashed long-time rival Maria Sharapova in the opening round on Monday, but was given a much sterner test by McNally on the 17-year-old’s first main-draw appearance at Flushing Meadows.

McNally, ranked 121st in the world, constructed some excellent points as she tried to move Williams around the court and it proved successful when she claimed the first break point of the match for a 6-5 lead.

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After fighting off three break-back points, McNally sealed the set at the second attempt to move halfway to a famous victory against one of the all-time greats, who had already won the 1999 US Open before McNally was born in November 2001.

Eventually Williams found a level closer to her best, breaking for a 4-2 lead in the second set and levelling after missing four set points on McNally’s serve.

The final set was a different story to the previous two, Williams winning 16 of the opening 17 points and needing little over 20 minutes to clinch victory.

Williams will find out her next opponent on Thursday. The meeting between Hsieh and Muchova was one of the many first-round matches cancelled on Wednesday after rain decimated play in New York.

Earlier in Wednesday’s night session, Australian second seed Ashleigh Barty battled past American Lauren Davis in straight sets.

The French Open champion, 23, saved a set point in the second before taking her fourth match point to win 6-2 7-6 (7-2) on Louis Armstrong Stadium.