Wednesday’s notes from Melbourne Park

NADAL INJURY REMAINS A MYSTERY

World number one Rafael Nadal Wednesday said he didn't know the exact nature of the injury problem which saw him slump out of the Australian Open quarter-finals.

Nadal was troubled from just the second game against David Ferrer, when he emerged from a medical timeout with his left thigh heavily strapped. But he insisted he didn't know what the problem was.

"I can't tell you because first of all I don't know," he told journalists.

"I tried my best all the time but it's obvious I didn't feel at my best. I had a problem at the very beginning and after that the match was almost over."

The 24-year-old, who was bidding to unite all four Grand Slam titles for the first time in 42 years, looked in discomfort throughout the match and was well below-par in losing 6-4, 6-2, 6-3.

Nadal withdrew injured from last year's quarter-finals, also on Australia Day, when he retired from his match against Andy Murray with knee tendinitis.

BAD TIME TO LEAVE

Rules are rules, but Alexandr Dolgopolov's coach tried to explain that he was needed on center court.

The coach, Jack Reader, attempted to negotiate his way back into the player's box and when he was finally allowed back to his seat, he was stunned.

"What's going on here?" the coach asked when he got back.

When Reader left his seat, the 22-year-old Dolgopolov had forced No. 5 Andy Murray to a fourth set. The unpredictable Ukrainian with an erratic but effective style had gotten the better of Murray in a 36-stroke rally in the third set, saving three break points and then going on to win a tiebreaker.

But if fans - or coaches - leave during a match they are required to wait until odd-numbered game changeovers to enter the stadium to avoid disrupting players.

When Reader was allowed back in after the third game of the fourth set, Dolgopolov was down 3-0.

"He went to the toilet," Dolgopolov said he learned later, saying he had looked for his coach but didn't see him. "They were giving him a hard time getting back because they were saying, 'You don't have a box pass.' He's like, 'Look, it's coach Dolgopolov.' Yeah, he wasn't there for a few games."

Dolgopolov has emerged as one of the up-and-coming stars of this year's Australian Open, reaching the quarterfinals on his first appearance in Melbourne. He caused two of the tournament's biggest upsets beating No. 13 Jo-Wilfried Tsonga in the third round, followed by No. 4 Robin Soderling in the fourth round.

"You look up to see someone cheer for you and it makes you feel better," Dolgopolov said. "But if he's not there, he went somewhere for his business. I mean, it's not like a tragedy or anything."

Murray won the fourth set, beating the Ukrainian 7-5, 6-3, 6-7 (3), 6-3.

"Getting ahead early in the fourth set made a big difference," Murray said.

VEGEMITE, AN ACQUIRED TASTE

What better way to mark Australia's national day than with a little Vegemite.

Australians grow up eating the iconic spread, a salty, slightly bitter thick brown paste. It is often said that appreciating the acquired taste of Vegemite is only possible if you start young.

"I'll try it," Vera Zvonareva told a television interviewer from ESPN who offered her some bread thickly slathered with Vegemite to celebrate Australian Day after her victory.

"I tried it like five years ago, but maybe it's different now," the Russian said, looking a bit concerned.

She took a small bite, paused and then winced. Words escaped her.

"Ohhhuhhhmmmm," she said, politely handing the plate back and it was quickly taken away.

US Open champion Kim Clijsters was offered a dab of Vegemite on bread after her quarterfinal win by former American star Pam Shriver, who is commentating for the sports channel.

Clijsters is now married with a child but is known here as "Aussie Kim," a nickname that dates back a few years to the time she was engaged to Australian player Lleyton Hewitt. She showed that she knows a thing or two about Vegemite.

"You don't put butter on?" Clijsters asked Shriver, who took a bite herself.

"Don't they usually toast their bread?" Clijsters asked, knowingly. She did not eat any Vegemite.

With Sapa-AP and Sapa-AFP