MELBOURNE, Australia — Rafael Nadal’s quest to complete his “Rafa Slam” at the Australian Open started with a first-round victory today that lasted only 47 minutes and helped conserve plenty of energy.

Nadal led 6-0, 5-0 when his Brazilian opponent, Marcos Daniel, retired because of a left knee injury.

The 24-year-old Spaniard sympathized with Daniel. Nadal retired from the last Australian Open because of an injured knee in a quarterfinal loss to Andy Murray. But he recovered quickly and won the next three majors and is now aiming to become the first man since Rod Laver in 1969 to hold all four Grand Slam trophies at the same time.

“It’s terrible feeling, for sure. I wish him all the best for a fast recovery,” Nadal said after the match. “Last year was a really difficult time when I played this tournament. I came back here playing well … but to go out like that was hard mentally.

“Finally, I had a very good season in 2010.”

Good season is an understatement. Nadal won the French Open, then Wimbledon, then finally claimed his first U.S. Open title.

“I came back after a difficult situation. Winning Roland Garros was very important, it allowed me to play the rest of the season with a little bit more calm.”

Vera Zvonareva began her bid to reach a third consecutive Grand Slam final with a commanding 6-2, 6-1 win over Sybille Bammer.

Zvonareva, who lost to Serena Williams in the Wimbledon final and Kim Clijsters in the U.S. Open final last year, dominated the first set against the 30-year-old Bammer and tightened her grip on the match in the second. She conceded only four points in the first four games of the second set and didn’t allow the Austrian to hold until the sixth game.

“It’s tough to play your best tennis in the first match. The most important thing is I’ve done what I needed to do and moved through to the next one,” Zvonareva said.

Nadal’s easy run to the second round came a day after his chief rivals, Roger Federer and Novak Djokovic, got their campaigns started with straight-sets wins.

Federer, the defending champion, dismantled Lukas Lacko 6-1, 6-1, 6-3. The 16-time Grand Slam champion is aiming to become only the second man to win the Australian Open five times; Roy Emerson won six.

Djokovic had no trouble against Marcus Granollers, soundly beating the 24-year-old Spaniard 6-1, 6-3, 6-1.

Eighth-seeded American Andy Roddick cruised to a 6-1, 6-2, 6-2 win over Jan Hajek of the Czech Republic.

“I feel healthy and strong for the first time in a while,” said Roddick.

In the women’s draw, fourth-seeded Venus Williams advanced 6-3, 6-2 over Sara Errani of Italy.