WASHINGTON, Aug. 12 (Xinhua) -- World No. 1 Novak Djokovic had a difficult beginning at the Western and Southern Open on Tuesday.
The Serbian needed three sets to beat Gilles Simon 6-3, 4-6, 6-4 to advance to the second round.
Djokovic was leading 2-1 in the second set, but Simon managed to come back by breaking twice.
Simon was unable to hold his serve in the seventh game, allowing Djokovic to break to seal the victory in the decisive set.
Djokovics will face the winner between Tommy Robredo and Sam Querrey in the next round.