The Serbian, a 17-time Grand Slam winner, is into his 10th French Open semi-final - but has only once won the title at Roland Garros, in 2016.

Both players had 13 break points but Djokovic was more clinical, converting six compared to the Spaniard's three, and that proved the difference.

The world number one and top seed ended up a 4-6, 6-2, 6-3, 6-4 winner and will play Stefanos Tsitsipas of Greece in the last four.

Tsitsipas, seeded fifth, is into just his second Grand Slam semi-final following a straight-sets win over Andrey Rublev of Russia.

The 22-year-old had lost to Rublev in the German Open final two weeks ago, but served well in Paris, winning 80 per cent of points when his first service landed in and being broken only once.

Tsitsipas triumphed 7-5, 6-2, 6-3 and has not dropped a set since round one, when he came back from two sets down to beat Jaume Munar of Spain.

In the women's singles, two past Grand Slam winners secured semi-final berths today.

Petra Kvitová, who last reached the French Open semi-finals eight years ago, powered past Laura Siegemund of Germany 6-3, 6-3.

The straight-sets victory means the Czech, who has twice won Wimbledon, has still not dropped a set this tournament.

She will play Sofia Kenin of the United States for a place in the final.

Kenin, seeded forth, needed three sets to overcome compatriot Danielle Collins.

Four of her five matches this fortnight have gone to three sets.

The reigning Australian Open champion beat Collins 6-4, 4-6 ,6-0.

In contrast to the pedigree of Kenin and Kvitová, the other women's semi-finalists - 19-year-old Iga Świątek of Poland and Argentina's Nadia Podoroska - have both achieved career-best performances at a Grand Slam already.

Both women's semi-finals are scheduled for tomorrow, with the men's semi-finals to follow on Friday (October 9).