Defending US Open champion Rafael Nadal sent close friend David Ferrer into Grand Slam retirement on Monday when his veteran compatriot was forced to quit their first round match with injury.
Former winners Andy Murray and Stan Wawrinka and Wimbledon finalist Kevin Anderson progressed to the second round in New York.
Ferrer, a former world number three but now standing at a lowly 148, called it quits on a hot and humid night on Arthur Ashe Stadium despite leading 4-3 with a break in the second set after twice receiving treatment on a left leg injury.
Top seed Nadal had taken the opener 6-3.
“This is my last Grand Slam,” said Ferrer who was runner-up to Nadal in the 2013 French Open final.
“I have great memories of this tournament and I am just sorry that I couldn’t finish it tonight.”
Ferrer, 36, will play his last tournament on home ground in Madrid next year.
“I am very sorry for David and sad for him,” said Nadal.
“We are close friends and have shared great moments — the Roland Garros final and Davis Cup wins.
“He is one of the greatest players to have come from our country. He’s a great person and great player.”
Nadal, chasing his 18th Grand Slam title, will face Canada’s Vasek Pospisil for a place in the last 32.
Nadal’s potential semi-final opponent, Argentine third seed and 2009 champion Juan Martin del Potro, also reached the second round with a 6-0, 6-3, 6-4 win over American qualifier Donald Young.
For Del Potro, whose career since his maiden Grand Slam triumph nine years ago has been decimated by wrist problems, it was his 30th career win at the tournament.