Djokovic defeated Florian Mayer 6-3, 7-5, 6-4 without dropping serve. Djokovic took a very healthy 77 percent of the points on serve and faced only three break points.
He opened the match with a four-point game serving and used a break in the second game for an early lead. Djokovic, after fighting off a sixth-game break point, broke Mayer's serve in the 11th game of the second set.
Djokovic had a break to open the third set and, after stopping two break chances of Mayer's to go up 5-3, served out for the match.
Ferrer had one blip in a 6-1, 4-6, 7-5, 6-2 victory over Martin Alund. He took 72 percent of the points serving and had just one break -- a miscue that he fed with three double faults and that cost him the second set.
Seventh-seeded Tomas Berdych didn't lose his serve while beating Martin Klizan 6-3, 6-4, 6-4 and No. 8-seeded Juan Martin del Potro advanced with a 6-2, 7-5, 6-1 win over Alberto Ramos by cashing in six of his eight break opportunities.
Ninth-seeded Richard Gasquet took a 6-7 (2-7), 6-4, 7-5, 6-4 win over Marcel Granollers while No. 12-seeded Kei Nishikori claimed a 6-2, 6-4, 6-3 decision over Matthew Ebden. Tommy Haas, the No. 13 seed, was a 6-3, 7-5, 7-5 winner over Dmitry Tursunov.
Three seeds exited play Tuesday. Feliciano Lopez ousted 19th-seeded Gilles Simon 6-2, 6-4 7-6 (13-11) three days after he beat Simon in the final of the Aegon International. Ivan Dodig moved into the second round when 16th-seeded Philipp Kohlschreiber retired in the fifth set with an injury. Bernard Tomic knocked off 21st-seeded Sam Querrey, holding on in five sets after winning tiebreakers in the first two sets.
Other seeded players gaining the second round with wins Tuesday were No. 17 Milos Raonic, 23rd-seeded Andreas Seppi, 26th-seeded Alexandr Dolgopolov, No. 27 Kevin Anderson, 28th-seeded Jeremy Chardy and No. 29 Grigor Dimitrov.
Unseeded players advancing were Denis Kudla, Leonardo Mayer, Jesse Levine, Jan-Lennard Struff, Michael Llodra, James Blake and Michal Przysiezny, Paul-Henri Mathieu, Santiago Giraldo, Daniel Brands, Igor Sijsling, Jimmy Wang, Grega Zemlja, Go Soeda,Roberto Bautista-Agut and Bobby Reynolds, who earned a second-round slot opposite Djokovic.
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