Rafael Nadal had to pause for a few moments, visibly emotional, while addressing the crowd after his loss in the fourth round at the Madrid Open.
As chants of "Rafa, Rafa, Rafa" echoed around, the five-time champion in Madrid made a farewell speech following a 7-5 6-4 loss to the 31st-ranked Jiri Lehecka on Tuesday (Wednesday AEST).
It was probably his last official match at the tournament in the Spanish capital.
"This is a difficult day when it arrives, but it's a reality. My body and my life had been sending me signs for some time," Nadal said.
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READ NOW"I was able to say goodbye playing on this court, one of the most emotional ones for me. Madrid at times has been more important to me than a grand slam. The memories here will stay with me forever."
After the match, tournament organisers unfurled five banners for each of Nadal's titles in Madrid - 2005, '10, '13, '14 and '17. They also showed a video of his highlights, as his wife and sister shed tears in the stands.
"It's been a gift what you've done for me during the 21 years that I've played here," said the 37-year-old Nadal, a winner of 22 grand slam singles titles. "All I can say is 'thank you.'"
Nadal had not lost to a player ranked outside the top 20 on clay since falling to Pablo Cuevas in 2016 at Rio de Janeiro. He was seeking his 60th win in Madrid and the 100th ATP 1000 quarter-final of his career.
Earlier, the player who Spanish fans hope will take over Nadal's reign, Carlos Alcaraz, needed nearly three hours to beat Jan-Lennard Struff 6-3 6-7 (5-7) 7-6 (7-4).
Both Spaniards are coming off injuries and are trying to get back in shape ahead of next month's French Open.
The 20-year-old Alcaraz had missed tournaments in Monte Carlo and Barcelona, and the 37-year-old Nadal had played two matches in Barcelona after not playing competitively in nearly three months.
Second-seeded Alcaraz squandered four match points while serving for victory at 5-3, but converted on his first opportunity to seal the victory in the deciding tiebreak at the Caja Magica centre court.
Alcaraz is trying to become the first player to win three straight Madrid Open titles. The world No. 3 will next face seventh-seeded Andrey Rublev at the claycourt tournament.
Top-seeded Jannick Sinner defeated 16th-seeded Karen Khachanov 5-7 6-3 6-3 to reach the Madrid quarter-finals for the first time. He is the only player to reach the last eight at all four ATP 1000 events this season.
Francisco Cerundolo, ranked 22nd, upset two-time champion Alexander Zverev 6-3 6-4 for his third career win over a top-five player. Cerundolo next plays Taylor Fritz after the American defeated Hubert Hurkacz 7-6 (7-2) 6-4.
Third-seeded Daniil Medvedev was given the run-around by Alexander Bublik before winning 7-6 (7-3) 6-4. The Russian next plays 30th-seeded Lehecka.