Next up for Nadal, champion here in 2005, will be 15th-ranked Richard Gasquet after the Frenchman overcame 23 aces by American Mardy Fish to win 6-7 (3), 6-4, 6-3.
"I'm probably playing with less pressure than usual so whatever happens, things are good,'' said Nadal, who has a slight nag in his right leg despite three weeks of rest coming in.
Nadal received a four-set test from Gulbis en route to the Wimbledon title, and Tuesday's match was similarly troubling for the Spaniard. But Gulbis often followed a crisp winner with an unforced error.
At 5-5, Gulbis responded to Nadal's double-break chance with an ace then double-faulted. In the next game Nadal saved a double-break chance on the run and closed out the first set when Gulbis volleyed into the net.
Nadal, who has never been a fan of the Spanish capital's high altitude and the extra speed it brings to the hard court, had trouble keeping up with the Latvian as he stuck his shots, including a backhand down the line to break for 2-0 in the second.
A ragged Nadal eventually netted to force a deciding set in the mainly baseline contest.
"He played very well in the second set but all the match was very tough because he played very aggressive,'' Nadal said.
Several crosscourt forehands gave Gulbis a break opportunity in the third game, but Nadal held and broke in the next game as Gulbis smashed a forehand long. Nadal served out and pumped his fists in relief at the end of his 2-hour, 22-minute opening match.
He has a 5-0 record against Gasquet.
"My record is good against him but it's always a tough match with him,'' the Olympic champion said.
In other second-round matches, U.S. Open finalist Andy Murray advanced, but 11th-seeded James Blake and No. 13 Fernando Verdasco lost.
Murray moved on when Simone Bolelli of Italy retired with an apparent shoulder injury while trailing 6-0, 2-1.
"I've been playing really, really well in practice the last few weeks, better than I was playing throughout the summer,'' said Murray, who picked up his first Masters Series title in Cincinnati in August. "I'm probably mentally fresher now than the U.S. Open.''
Murray will next play Marin Cilic of Croatia, who beat Verdasco 6-2, 6-3.
Gilles Simon of France won 3-6, 6-1, 6-4 to keep Blake winless in five appearances at the tournament. Simon saved four break points in the second set and converted two of his own before dominating the final set.
Blake has only a few tournaments left to qualify for the Masters Cup. He's in ninth place in the standings for the top-eight event.
In first-round play, the winners included French Open semifinalist Gael Monfils, American qualifier Robby Ginepri, Spanish qualifier Marcel Granollers, Philipp Kohlschreiber of Germany, Jarkko Nieminen of Finland, Victor Hanescu of Romania, Robin Soderling of Sweden, and Feliciano Lopez of Spain.
Usain Bolt Is A Blanco
Fish advances to 2nd round at Madrid Masters
