Djokovic, the reigning Australian Open champion, outlasted German Denis Gremelmayer 4-6, 6-3, 7-5, 6-2.
Sixth-seeded David Nalbandian of Argentina, No. 7 James Blake of the United States and No. 10 Andy Murray of Great Britain also advanced to the second round.
Nalbandian rolled over countryman Carlos Berlocq, 6-2, 6-4, 6-1; Blake defeated Rainer Schuettler of Germany 6-4, 6-1, 7-6 (7-3); and Murray won a five-setter over 17-year-old Jonathan Eysseric of France, 6-2, 1-6, 4-6, 6-0, 6-2.
"I felt good," Blake said. "Definitely had a pretty good claycourt season so far this year, and it could always to be a little better. Hopefully this will prove I can put a bunch of wins together."
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