Martin served 14 aces and won 48 points at the net as he served and volleyed his way past Morocco's Younes El Aynaoui 6-3, 6-2, 4-6, 6-4.
Although the 12th seed was the best known male player on the day's schedule, he was forced to share the spotlight with a relatively unknown South African qualifier who had never won a Grand Slam match.
David Nainkin, ranked 215 in the world, stunned his ninth-seeded compatriot Wayne Ferreira, who had been running into form coming into tournament.
Ferreira, ranked No 7 in the world after last week's title triumph in Toronto that included wins over Martin and Thomas Enqvist, found his impressive 18-4 record on hard courts this summer counted for nothing as he lost 6-4, 6-4, 2-6, 7-5.
''I felt like I've been playing tennis every day for the last five months,'' said Ferreira, who also fell to a qualifier in the first round here last year. ''It was very difficult to get motivated to play mentally. When that doesn't happen, your physical side kind of disappears."
Ferreira joined a list of first-round seeded casualties, including Richard Krajicek (No 5), Alberto Costa (No 14) and Marc Rosset (No 15).
In only the third match of his career against a top-10 player, Nainkin had no trouble finding the kind of motivation that was lacking in his opponent.
''I really wanted to win. I had a willpower that I didn't know I had," said the excited 25-year-old from Durban. The only other men's seed in action was Spanish clay court specialist Felix Mantilla, who was awarded a 17th seeding after the French Open champion Yevgeny Kafelnikov pulled out, apparently angry at his demotion in the seedings although he was also suffering from an injury.
Exiled to one of the smallest outside courts, Mantilla beat Brazil's Fernando Meligeni 6-1, 6-7, 7-6, 6-3 - the first win of his career on a hard court.
Monica Seles, the second seed and joint women's world No 1, reached the third round without hitting a ball. The 1991 and 1992 champion, who dropped only one game in her opening match, was scheduled to play Laurence Courtois of Belgium, but tournament officials announced about four and a half hours before the match that Courtois had pulled out because of a left knee bone inflammation, putting Seles into the next round on a walkover. Also through is Gabriela Sabatini, the 1990 champion, who beat Ann Grossman of the United States 6-2, 6-3.
Lindsay Davenport's magnificent summer shows little sign of coming to an end. The eighth-seeded American, who lost 20 pounds in a fitness campaign that helped carry her to an Olympic gold medal in Atlanta, dispatched Slovakian Henrieta Nagyova 6-0, 6-4 in just 49 minutes.Reuse content