Rafael Nadal reached the French Open final after his opponent Alexander Zverev needed to be taken off court in a wheelchair following a nasty fall.

A concerned Nadal went round to check on his opponent as a medic raced on to the court to help the German.

Fifth seed Nadal was leading 7-6 (10-8) 6-6 when Zverev left the court.

After a short break, Zverev returned on crutches and was given a warm hug by Spain's Nadal before the crowd rose in a standing ovation.

"It is very tough and I feel very sad for him," said 13-time champion Nadal.

"He was playing an unbelievable tournament. I know how much he is fighting for a Grand Slam - he will win more than one. I wish him all the very best.

"It is difficult to say a lot of things in this situation. For me to be in the final of Roland Garros is a dream but at the same time to finish that way is not nice.

"I was in a small room with Sascha [in the treatment room off court] and to see him crying was a tough moment."

Zverev's retirement put Nadal into Sunday's final, where he will play Norwegian eighth seed Casper Ruud or Croatian 20th seed Marin Cilic.

On his 36th birthday, Nadal has become the second oldest men's singles finalist in French Open history behind American Bill Tilden, who was 37 when he was runner-up in 1930.

Heartbreaking end to compelling match

Zverev's fall was a dramatic and heartbreaking end to a semi-final battle that had been intriguing if not compelling.

The 25-year-old German had lost the first set after being unable to take any of four set points from a 6-2 lead in the tie-break.

After missing the chance to serve out the second set, producing three double faults at 5-3, Zverev showed resilience to regroup.

In a set full of suspense, if not quality, he was about to have the opportunity to level in another tie-break.

Instead his ambitions of becoming a Grand Slam champion - at least now - were ended in the cruellest manner.

The seriousness of the situation was immediately clear, with Zverev screaming and signalling for help as he lay on the ground.

Medics quickly arrived and it seemed obvious he would not be able to continue once the wheelchair was called for.

A sombre mood hung in the air as the 15,000 crowd on Court Philippe Chatrier waited for news and it came when Zverev returned on crutches to shake hands with umpire Renaud Lichtenstein.

Almost the entire stadium stood up to give Zverev a thunderous round of applause, the player responding by lifting one of his crutches into the air.

Long scrap cut short by Zverev's misfortune

The unexpected ending brought an end to a scrappy match that had already lasted three hours and 13 minutes without the second set being concluded.

Nadal, who continues to battle a chronic foot injury, was far from his best in the opening set but showed his brilliance in the crucial moments to help win it.

The 21-time Grand Slam champion walked out to the match amid huge applause, before the crowd serenaded him with a rendition of 'Joyeux Anniversaire' - 'Happy Birthday' in French.

The party atmosphere quickly changed. Zverev broke Nadal's serve in the opening game of the match, with Nadal struggling on the slower conditions in humid conditions under the Chatrier roof on a rainy Paris afternoon.

Zverev moved 4-2 ahead with a service hold to love, showing his high level of confidence with powerful winners.

But he got tight when serving at 4-3 and Nadal broke as part of a run of three successive games that left Zverev serving to stay in the opening set.

The German came under pressure again, fending off three set points which his errors had helped create. But he survived, although he was then unable to take either of two break points himself in the 11th game.

It was left to a tie-break to separate the pair, where Nadal produced two forehand winners at crucial times that were almost unworldly.

Nadal saved Zverev's third set point with a whipped crosscourt forehand which left most in the crowd in awe and jubilantly celebrating, sealing the set at the sixth opportunity with a sensational forehand winner down the line.

A messy second set featured eight breaks of serve in the opening nine games. Nadal finally held serve for the first time in the set for 5-5 and another tie-break was necessary until agony struck for Zverev.