AFP - Stand down ladies. Japanese golf star and Asia-wide heart-throb Ryo Ishikawa, once nicknamed "The Bashful Prince", is spoken for, his mother has said.

Ishikawa, the object of passions right across the age spectrum, is set to introduce his potential fiancee, a junior high school classmate, at the Presidents Cup in Melbourne next month, Japanese media reported Tuesday.

"There exists a woman whom Ryo Ishikawa is going out with," his mother, who is also his manager, said in a statement to local media, asking them to refrain from overheated coverage of the golfer's "private matters."

"We would appreciate it if the people concerned will treat them with warm patience in order to help the two of them and avoid any trouble to sponsoring companies and competition officials," Yukiko Ishikawa said.

Ishikawa's family, friends and sponsors have been bothered by "news-gathering activities exceeding social norms in the form of making surprise night-time visits and shadowing," the statement said.

The Nikkan Sports said the golfer, who turned 20 last month, had been seeing the unnamed girlfriend for three years. The statement was issued as a weekly magazine was preparing to publish a story on their romance, the tabloid Yukan Fuji said.

Ishikawa refused to confirm the relationship when confronted by reporters Tuesday at a golf course in western Japan ahead of a tournament there this week.

"As I'm a pro golfer, I'd better answer questions just on golf at the golf course," said Ishikawa, who is winless so far this season. "As mentioned in the release, I can only say I'd appreciate it if you could show patience."

Ishikawa has been a hot marketing property since May 2007 when he became the the youngest men's winner on a major tour by lifting the domestic Munsingwear Open KSB Cup aged 15 years and eight months. He turned professional in 2008.

With his squeaky clean image, Ishikawa has attracted a huge gallery, many of them women, wherever he has played, giving a huge boost to the popularity of the men's game at home.

His commercial deals with more than 20 firms, including such giants as Panasonic and Toyota, are estimated to be worth more than three billion yen ($40 million).

With his powerful drive and daring short game, he has won nine tournaments at home -- but none in 18 outings so far this year. In April, he made the cut at the US Masters for the first time in three attempts and finished 20th.

Ishikawa is set to take his girlfriend to the Presidents Cup to mingle with other golf stars and their partners in social events, the Nikkan Sports said.

The biennial tournament pits a US team against players from the rest of the world, excluding Europe.