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 was outplayed early on 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 Djokovic has overturned a two-set deficit to win at a Slam.
However, he was clearly frustrated by Musetti, who 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.”
Musetti comes close to shock of tournament
From the very first point, when he nailed a backhand winner down the line, Musetti appeared to believe he belonged in such esteemed company and affirm the opinion of many that he is a star of the future.
Djokovic had not dropped a set in his opening three matches at Roland Garros, his serve broken just once all week, but Musetti ended that streak in a captivating first set.
Breaking back immediately after being broken to love, Musetti entertained the crowd with some inventive shots, including a stunning no-look backhand volley winner, to take it to a tie-break.
There he came from 4-1 down to earn three set points and while some Djokovic brilliance saved the first two, a stunning Musetti forehand into the corner of the court converted the third.
After breaking the Djokovic serve again early in the second set, a service game littered with errors nullified Musetti’s advantage.
But the youngster refused to buckle, a wrong-footing backhand down the line bringing applause from his opponent as Musetti forced another tie-break which he dominated 7-2 to the excited disbelief of the crowd.
At times, he had Djokovic running from corner to corner of the court – like the world number one regularly does to his rivals – but Musetti’s accuracy began to desert him in the third set.
The abdominal injury contributed further to his downfall as the 18-time Grand Slam champion ultimately proved too resourceful for a player who was ranked 360th in the world at the start of last year.
Nonetheless, it was difficult to shake the impression that this was just the start for Musetti, who beat 13th seed David Goffin in the first round and also owns wins over Stan Wawrinka, Kei Nishikori, Diego Schwartzman and Grigor Dimitrov in little more than a year on the senior tour.
“It’s unfortunate for a young player like him,” a magnanimous Djokovic added.
“He was unable to physically sustain the level, at least to give himself a chance to win this match, because he was in the driving seat for the first couple of sets.”
Djokovic shows heart of a champion
While many of the plaudits will head Musetti’s way, credit must also be given to Djokovic for not losing his head, having thrown everything at his opponent for two sets only to see it launched back with interest.
He turned up the aggression factor after losing the second-set tie-break and it immediately paid dividends with an early break in the third set.
That seemed to dishearten the Italian and, as Djokovic’s level grew, the teenager’s dropped.
While it might not have seemed so at two sets down, the test – after three comfortable wins – could be beneficial for Djokovic, who can only face seeded players from here on in to the final.
Bidding to make history as the first Open era player to win a second career Grand Slam by adding to his sole Roland Garros triumph, the Serb will surely take confidence from his fightback here.
He was dominant on serve throughout, conceding only four break points and saving two, with his only meaningful blip coming during the second-set tie-break that preceded his recovery.
“After I lost the second set and went out to change and came back, I just felt different. I was a different player,” Djokovic added.
Schwartzman fights way into quarter-finals
Earlier, Diego Schwartzman produced a stunning first-set recovery to set himself up for victory over Jan-Lennard Struff.
The Argentinian 10th seed trailed his unseeded German opponent 5-1 early on but saved six set points and then another in a lengthy tie-break, which he eventually won 11-9.
Schwartzman lost four successive games from 4-0 up in the third set but held on to win 7-6 (11-9) 6-4 7-5.
He will face either Rafael Nadal or Jannik Sinner in the quarter-finals.