The world number one elected to take to the court against Alexandr Dolgopolov of the Ukraine after suffering the heart-breaking blow at training in the morning.
His match, interrupted by the fourth rain shower of the day at the Monte Carlo Country Club, eventually ended with a 2-6, 6-1, 6-4 win and a pleading look to the Mediterranean skies from the distraught star.
Djokovic was said to be close to grandfather Vladimir and sheltered with him and other family members during the NATO bombing of Belgrade in 1999.
Results from the Monte Carlo Masters on Thursday (x denotes seeding):3rd rd
Andy Murray (GBR x3) bt Julien Benneteau (FRA) 6-5 - retired
Tomas Berdych (CZE x6) bt Kei Nishikori (JPN x12) 2-6, 6-2, 6-4
Jo-Wilfrid Tsonga (FRA x4) bt Fernando Verdasco (ESP x13) 7-6 (9/7), 6-2
Gilles Simon (FRA x9) bt Janko Tipsarevic (SRB x7) 6-0, 4-6, 6-1
Novak Djokovic (SRB x1) bt Alexandr Dolgopolov (UKR x16) 2-6, 6-1, 6-4
Rafael Nadal (ESP x2) bt Mikhail Kukushkin (KAZ) 6-1, 6-1
Robin Haase (NED) bt Thomaz Belluci (BRA) 6-2, 6-3
Stanislas Wawrinka (SUI) bt Nicolas Almagro (ESP x8) 6-3, 6-3