Rafael Nadal's record-breaking French Open career came to its likely end on Monday when the 14-time champion slumped to a demoralising first round defeat against Alexander Zverev.

Nadal, who turns 38 on June 3, went down 6-3, 7-6 (7/5), 6-3 to world number four Zverev, suffering only his fourth loss in 116 matches at Roland Garros since his 2005 title-winning debut.

It was the first time he had been defeated in Paris in the opening round and will again lead to questions over his long-term future in the sport.

"I don't know if this is the last time I will be here, I am not 100% sure but if it is then I wanted to enjoy it," said Nadal.

"The feelings today are difficult to describe in words."

Plagued by injuries, which had limited him to just four events since January last year, former world number one Nadal is now 275 in the rankings and was unseeded in Paris.

However, he insisted on the eve of the tournament that he was "100% keeping the door open" on his future in a sport which has brought him 22 Grand Slam titles.

In a repeat of the 2022 semi-final, which Nadal won when Zverev quit with ankle ligament damage, the Spaniard had his chances.

He was a break of serve up in the second and third sets, only to be pinned back on both occasions by his in-form 27-year-old opponent.

Chants of "Rafa, Rafa" had loudly echoed under the roof of Court Philippe Chatrier which was shut tight against the torrential rain sweeping across the grounds and bringing havoc to the schedule.

They subsided to silence when Nadal was broken to love in his opening service game and he was left to regret his inability to convert two break points in the fourth game.

Nadal saved two set points in the ninth game but surrendered the opener after 50 minutes when he buried a loose forehand into the net.

It was only the fourth opening set he had lost at Roland Garros.

Nadal broke for the first time in the match to lead 3-2 in the second set but couldn't back up the advantage and handed the break back to three-time semi-finalist Zverev as he served for the set.

A tense tie-breaker followed which the German claimed, buoyed by stretching to 5/3 on the back of a gruelling 19-shot rally.

Nadal dug deep and with the likes of Novak Djokovic, Carlos Alcaraz and Iga Swiatek having watched from the packed stands, he broke and held for 2-0 in the third set.

However, Zverev again roared back to level at 2-2 before a besieged Nadal had to save four break points in a 13-minute fifth game to stay in contention.

The effort was too much and a composed Zverev was soon 4-3 up and the match was over when Nadal fired a forehand wide and long.