Djokovic had to rally to upend sixth-seeded Czech Tomas Berdych 4-6, 6-3, 6-2 Saturday, but Nadal had an easier time beating Gilles Simon of France 6-3, 6-4.
Nadal, who has won seven consecutive Monte Carlo championships, ran his winning streak on the venue's clay courts to 41 in a row. He has not won a tournament, however, since the 2011 French Open.
Nadal holds a 16-14 advantage in the lifetime series against Djokovic, who played on despite the death of his grandfather in Serbia earlier in the week.
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