Nadal, of Spain -- who has won Monte Carlo eight years in a row and was seeded No. 3 this year -- advanced with a 6-3, 7-6 (7-3) victory over Jo-Wilfried Tsonga of France.
Top-seeded Djokovic, of Serbia, followed into the finals of the French Open tuneup by dispatching Italian Fabio Fognini 6-2, 6-1. Djokovic did not face a break situation in the match, which lasted 52 minutes.
Nadal had a tougher time with Tsonga, who saved three match points in the final set.
Nadal holds a 19-14 lifetime advantage against Djokovic and has won 46 consecutive matches on clay. The two have not met since Nadal beat Djokovic in the French Open final last year.
Celebrity Couples of 2014 [PHOTOS]