The world number 27 recovered superbly from two games down to win 5-11, 1-11, 11-4, 11-8, 11-7 at Grand Central Terminal.

Sobhy, the American number one who reached the Tournament of Champions final in 2016, was 2-0 up after just 20 minutes before Whitlock's roaring comeback.

"The last three games were a symbol of how I've been playing towards the end of last year," said Whitlock.

"I've really been working on everything, no injuries and being mentally and physically strong. 

"I was so lost out there and seeing it a bit late in those first two games and she was just so dominant. 

"I think I maybe saw the ball a bit quicker, hit the ball a bit cleaner on the racket and it just seemed to go my way.

"My coach said to me when I won yesterday, 'you’re playing Saturday night, prime time, under the chandeliers in Grand Central Terminal in front of one of the best crowds on the tour'. 

"Even if I'm the away player, I could hear people shouting my name, it just couldn't have been a better time to win."

Other women's second round results on day three included a comfortable 11-6, 11-1, 11-2 win for Egypt's top seed Raneem El Welily over Coline Aumard of France.

The 2017 world champion wrapped up the match in just 22 minutes.

Egypt's number three seed Nouran Gohar needed only 19 minutes in her match, however, defeating Alexandra Fuller of South Africa 11-5, 11-3, 11-4.

Camille Serme, France's fifth seed, had a much tougher examination as she needed five games to beat Egyptian Rowan Elaraby.

Serme came through 11-8, 3-11, 11-6, 9-11, 11-7 in just under an hour.

In the men's tournament, Joel Makin of Wales knocked out Peru's seventh seed Diego Elias.

The world number 12 came from behind twice to win 6-11, 11-7, 9-11, 11-6, 11-7 and book his place in round three.

"If you're outside the top eight then you can get these draws at any time," said Makin.

"I've had two of those in a row now but if I want to get up to the top eight then I have to start beating those guys and do it anyway, I'm glad I did that and hopefully the draw has opened up a little bit."

Egypt's second seed and 2017 world champion Mohamed ElShorbagy beat Ryan Cuskelly 11-5, 11-6, 11-5 and the Australian, who has won 16 PSA World Tour titles, announced his retirement following the defeat.

Karim Abdel Gawad, Egypt's third seed who won the world title in 2016, advanced after seeing off Iker Pajares Bernabeu of Spain 3-11, 11-6, 12-10, 11-6.

Germany's sixth seed Simon Rösner knocked out New Zealand's Campbell Grayson 11-8, 11-2, 11-4. 

The tournament resumes tomorrow.