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* Date-Krumm oldest singles winner
* Made Melbourne Park debut in 1990
MELBOURNE, Jan 15 (Reuters) - When Kimiko Date-Krumm first played at the Australian Open some 23 years ago, she beat American Pam Shriver on her way to the fourth round at the year's first grand slam.
Four year's later, she ousted Conchita Martinez to reach the semi-finals at Melbourne Park only to go down 6-3 6-3 to eventual champion Steffi Graf.
Shriver, Martinez and Graf are all many years into retirement now but Date-Krumm plays on and on Tuesday became the oldest winner of a women's singles match at the grand slam.
It was no ordinary victory, either, as the 42-year-old Japanese produced the biggest shock of the tournament so far to oust 12th seed Nadia Petrova 6-2 6-0 in the first round.
Date-Krumm, ranked 100th in the world, said entering the record books meant little to her and she played simply for enjoyment these days.
"I'm very happy to win today, but I don't play for the records," she told reporters. "Even when I lose, I still enjoy it. Of course, every time I lose ... it's tough. But still I enjoy playing.
"I love tennis," she added. "I like practice. I like games. I like the tour. I'm enjoy it a lot."
Like those Japanese who routinely survive well past their 100th birthdays, Date-Krumm is constantly asked about the secret to her longevity.
Certainly, a 12-year absence from the game from 1997 helped extend her career, she said, and Tuesday's victory was certainly not built on any mysterious Japanese super foods.
"I don't eat so much Japanese food when I'm travelling," she said. "I love to eat Japanese food, of course, but the quality is different when I'm travelling outside Japan.
"So last night I ate pasta."
Date-Krumm joked that she was now older than the mothers' of many of her rivals on tour and did have to make allowances in her lifestyle because of her age.
"I just eat a lot, I sleep a lot," she said. "Because always after the match or after the practice I'm tired, so I need time to recover a lot. So I sleep a lot, I eat healthy foods, I drink a lot. It's a simple life. That's it. Nothing special."
The win handed Date-Krumm a second round tie against Shahar Peer of Israel and, even if she loses, there is no reason to suspect that her 12th Australian Open will be her last.
"The season has just started, so I try to continue to end of year," she said. "But I don't know. Something like a big injury might happen, of course, so I cannot continue. And then - still, I don't know." (Reporting by Nick Mulvenney, editing by Patrick Johnston)