Roger Federer and Serena Williams were given the royal seal of approval after dazzling performances at the Australian Open Thursday.

Britain's Prince William was in the stands at the Rod Laver Arena admiring the Swiss master's win over Romania's Victor Hanescu 6-2, 6-3, 6-2 in the second round.

Federer later thanked the Prince for attending and shared a private moment with him before Serena Williams and her mother Oracene posed for a photograph with the second in line to the British throne.

"He was happy he could make it. I'm not gonna tell you everything he just said to me. You've got to have a little bit of a secret," Federer told a news conference.

"He shook a lot of hands, and I knew mine was one more. From what I've heard, I think he met Serena and myself."

Federer's polished display dispelled any doubts about his prospects of winning the year's first grand slam after he survived a scare in his first match with Igor Andreev.

"It's still early on in the tournament," he said. "You sometimes don't have to force the issue every single time."

Serena had earlier joined elder sister Venus in the third round as the main contenders continued to move safely through the draw.

Serena had no problems defeating Czech Petra Kvitova 6-2, 6-1 and is steadily improving as she tries to defend the title she won last year.

Venus Williams cruised to a 6-2, 7-5 victory over Sybille Bammer of Austria.

"I thought today was a little bit better than my match in my first round," Serena said. "I felt like I was moving better and I had better energy. Yeah, just felt all around a lot better."

Serbia's Novak Djokovic, the 2008 champion, survived a shaky start to win while in-form Russian Nikolay Davydenko and Australia's Lleyton Hewitt advanced in straight sets.

Denmark's Caroline Wozniacki also sailed through, beating Germany's Julia Goerges 6-3, 6-1 but, in a tournament bereft of major upsets, there were at least two surprises to spice things up.

The former world No. 1 Ana Ivanovic bowed out after a 6-7, 7-5, 6-4 loss to unseeded Argentine Gisela Dulko while Marcos Baghdatis defeated Spain's David Ferrer, the 17th seed.

Rollercoaster

Baghdatis has been plagued by injuries since his rollercoaster ride to the 2006 Australian Open final but showed he is getting back to his fighting best after winning 4-6, 3-6, 7-6, 6-3, 6-1.

"I saw a window open, so that's how it went," the Cypriot said.

Ivanovic made the final in Australia in 2008 and won the French Open that same year but her career has been in freefall ever since and she has slipped to 21st in the rankings despite trying desperately to resurrect her fortunes.

"It's a process. I think I just have to be patient," she said.

"Some matches it's there, some not. I just have to sort of keep my head up and try to improve."

Djokovic was unusually tentative at the start of his match but was always too streetwise for Switzerland's Marco Chiudinelli, winning 3-6, 6-1, 6-1, 6-3.

"I managed to make that transition from being defensive to being offensive and changing pace and holding the game," Djokovic said.

Davydenko steam-rollered Ukraine's Illya Marchenko 6-3, 6-3, 6-0 to maintain his unbeaten start to the year as he chases his maiden grand slam title while Hewitt survived a dogged challenge from American Donald Young to win 7-6, 6-4, 6-1.

Australian teenager Bernard Tomic received a dressing down from organizers after he blamed his second-round loss on the schedule. The 17-year-old was beaten in five sets by Croatian Marin Cilic on Wednesday in a match that finished well after 2am.

"I'm not trying to make any excuses, but I go to sleep at like nine, 10 normally. It's way past my bedtime," he said.

"If there doesn't become a change in his behavior, it becomes extremely hard for him to excel at the top echelons of the sport," Australian Open director Craig Tiley said.