Defending champion Novak Djokovic is through to the US Open semi-finals after a knee injury forced Jo-Wilfried Tsonga to retire as he trailed 6-3 6-2.
Djokovic has completed just two of five matches in New York, benefiting from a walkover and two retirements.
He will face another Frenchman in the last four after Gael Monfils beat compatriot Lucas Pouille 6-4 6-3 6-3.
“This was the scenario that I needed and I wished for,” said Djokovic, who has faced his own health issues.
The Serbian world number one arrived at Flushing Meadows nursing injuries to both his left wrist and right elbow.
Second seed Andy Murray will be in action today against Kei Nishikori before Juan Martin del Potro and Stan Wawrinka play the last of the quarter-finals.
In the women’s draw on Tuesday, Denmark’s Caroline Wozniacki beat Anastasija Sevastova 6-0 6-2 in another match marred by injury, with the Latvian severely hampered by a twisted ankle.
Wozniacki won easily to set up a semi-final against German second seed Angelique Kerber, who beat Italy’s Roberta Vinci 7-5 6-0.
World Number One Serena Williams will be in action against fifth seed Simona Halep today, while the last quarter-finals draw will be between Tenth seed Karolina Pliskova and Croat Ana Konjuh.