Djokovic reached his 40th Grand Slam semi-final when he defeated Italy's Matteo Berrettini 6-3, 6-2, 6-7 (5/7), 7-5. The Serbian booked his place in the last four in Paris for the 11th time.
Earlier, Nadal, the 13-time champion, beat Argentina's Diego Schwartzman 6-3, 4-6, 6-4, 6-0 to make the semi-finals for the 14th time.
A look at the numbers:
Overall: Djokovic leads 29-28
On clay: Nadal leads 19-7
At French Open: Nadal leads 7-1
At all Grand Slams: Nadal leads 10-6