The eighth seed captured hearts last year when she went on a tremendous run to a first Grand Slam title at the age of 19, but was unable to topple the in-form 17th seed today, who won the tie 6-4, 6-4 on the showpiece Court Philippe-Chatrier.

Sakkari has now defeated each of last year's finalists in back-to-back rounds, having beaten fourth seed Sofia Kenin of the United States in straight sets last time out.

She is one of two Greek semi-finalists, joining Stefanos Tsitsipas, who yesterday booked a place in the men's singles final four.

Next up for Sakkari is unseeded Czech Barbora Krejčíková, who overcame American teenager Coco Gauff in straight sets.

Krejčíková, who previously knocked out Ukrainian fifth seed Elina Svitolina and ex-Grand Slam winner Sloane Stephens of the US, won 7-6 (8-6), 6-3 today.

Sakkari is the highest seed remaining, and two of the semi-finals are unseeded.

In the men's singles, Nadal and Djokovic each advanced in four sets to book a 58th meeting of the pair.

Spain's Nadal was in action first and defeated 10th seed Diego Schwartzman of Argentina 6-3, 4-6, 6-4, 6-0.

It marks the 14th time Nadal has made the semi-finals of the tournament - with the "King of Clay" previously winning the French Open every time he has reached the final four. 

Nadal's 13 French Open titles are a record for a major tournament, while victory at Roland Garros would give him 21 Grand Slam crowns in total - surpassing Swiss star Roger Federer for the outright men's lead.

Djokovic, who lost to Nadal in last year's final, was pushed hard by Italy's Matteo Berrettini in the night game on Court Philippe-Chatrier - so much so that it went beyond the 11pm local curfew, meaning fans had to go home before the end.

When they were slow to leave, the players were sent off the court and play suspended until the arena could be cleared.

A night curfew is among the measures in place in France in response to the coronavirus pandemic.

Following the delay, Djokovic was able to seal a 6-3, 6-2, 6-7 (5-7), 7-5 win, and the world number one let out a huge roar when the final point was over.

French Sixth seeds Nicolas Mahut and Pierre-Hugues Herbert expectedly progressed to the semi-finals of the men's doubles following a 7-6 (7-5), 6-1 victory over Bosnia and Herzegovina's Tomislav Brkić and Serbia's Nikola Ćaćić.

In the other tie, Colombian second seeds Juan Sebastián Cabal and Robert Farah won 6-2, 6-7 (3-7), 7-5 against the ninth seeds, Germany's Kevin Krawietz and Horia Tecău of Romania.

In the women's doubles quarter-finals, Argentina's Nadia Podoroska and Irina-Camelia Begu of Romania defeated Croatian Petra Martić and American Shelby Rogers 6-3, 4-6, 6-2.

Bernarda Pera of the US and Pole Magda Linette are also through following 7-5, 4-6, 6-2 win over Anastasia Pavlyuchenkova of Russia and Kazakhstan's Elena Rybakina.

Unseeded Russians Elena Vesnina and Aslan Karatsev are through to the final of the mixed doubles after a 6-4, 6-1 victory over third seeds Wesley Koolhof and Demi Schuurs of The Netherlands, and will now face Britain's Joe Salisbury and American Desirae Krawczyk for the title.

Salisbury and Krawczyk made the final after their semi-finals opponents, Giuliana Olmos of Mexico and Cabal, withdrew.

Women's singles semi-finals headline tomorrow's play.