The world number 19 lost the opening game but showed impressive resilience in winning an 82-minute encounter.

The 29-year-old used his speed and agility to force a high tempo from the outset.

He held off a late Willstrop surge to triumph 5-11, 11-9, 10-12, 11-6, 11-9 and set-up a second round clash with German Simon Rösner.

"I think the US Open is one of my favourite tournaments - I love coming to play here," said Salazar.

"I worked really hard in pre-season and this is a good start for me. 

"To beat a really top player like James you have to play your very best and some more, so I'm really happy with my performance."

Egypt's Salma Hany produced another surprise result today at England's expense by defeating NetSuite Open winner and seventh seed Sarah-Jane Perry.

The 21-year-old world number 19 won 11-7, 11-3, 12-14, 11-6 and will next face compatriot Nour El-Tayeb.

"I'm very happy with the performance today," she said.

"SJ has been playing really well recently but I knew I had to keep the ball tight as much as I could and not give her many opportunities."

Other top ranked players had no such problems.

Men's second seed and defending champion Mohamed Elshorbagy of Egypt won 11-9, 11-8, 11-4 against Cameron Pilley of Australia.

England's 2007 winner and last year's beaten finalist Nick Matthew also eased past Zaher Mohamed of Egypt, 11-7, 11-5, 11-6.

Top women's seed Nour El-Sherbini thrashed fellow Egyptian Mariam Metwally 11-9, 11-2, 11-7 while three-time former champion Nicol David of Malaysia overcame Australia's Donna Urquhart 11-8, 11-4, 6-11, 11-5.

Action at the World Series event will continue tomorrow.