Dimitrov claimed a 7-6 (8-6), 6-7 (8-10), 6-3 victory to beat Djokovic for the first time in his career. It was just the third defeat this year for Djokovic.
Dimitrov took the last four points of the first tiebreaker, fighting off two set points, and was down 5-2 in the second before rallying, denying Djokovic to win any of the three set points he had. Dimitrov posted a third-game break in the third set to move ahead and added his fourth break of the day to assure the win in 3 hours, 5 minutes.
Defending champion and No. 2-seeded Roger Federer advanced with a 6-3, 6-3 win over Radek Stepanek with four breaks, including three in the second set. Federer improved to 12-2 lifetime versus Stepanek.
Daniel Gimeno-Traver eliminated No. 8-seeded Richard Gasquet 7-5, 3-6, 6-4 and Fernando Verdasco took out 12th-seeded Milos Raonic 6-4, 2-6, 7-6 (9-7) in other second-round upsets but No. 16-seeded Gilles Simon, who will next go against Murray, beat Jeremy Chardy 6-4, 7-6 (7-5).
The first round was completed and Juan Monaco ousted ninth-seeded Janko Tipsarevic 7-6 (7-5), 6-3 while 13th-seeded Tommy Haas routed Andrea Seppi 6-1, 6-2 and 15th-seeded Stanislas Wawrinka got past Marius Copil 6-4, 6-4.