Novak Djokovic avoided a shock fourth-round exit at the French Open after fighting back from two sets down against teenager Lorenzo Musetti.
The world number one looked out of sorts before rallying, leading 6-7 (7-9) 6-7 (2-7) 6-1 6-0 4-0 when the Italian, 19, retired with an injury.
World number 76 Musetti, playing in his first Grand Slam main draw, was given a standing ovation as he left the court.
Djokovic will face Italian ninth seed Matteo Berrettini next. It is the fifth time that has overturned a two-set deficit to win at a Slam.
However, he was clearly frustrated by Musetti, was able to match him shot-for-shot in the opening stages.
The teenager began to struggle with what appeared to be an abdominal injury and, after winning just four points in the fourth set, took a medical time-out before retiring after losing 13 successive games.
“I like to play young guys in the best-of-five because even at two sets down, I feel I still have my chances,” Djokovic said.
“I feel physically fit, I have won most of my five-setters and that experience helps. It’s unfortunate for him to have to retire but I could see he was struggling physically.”