SUSONO, Japan (AP) _ Hideaki Kase shot his second straight 4-under-par 67 Friday to take a one- stroke lead after two rounds of the Asahi Beer-Golf Digest tournament.

Yoshinori Mizumaki, with a second-round 68, was alone in second place.

Another two strokes back at 137 were first-round leader Futoshi Irino, who shot a 71, and Harumitsu Hamano, who had a 69.

Hale Irwin, this year's U.S. Open champion, and 1987 Masters champion Larry Mize each had a second straight 70 that left them in a group of 12 at 140.

Scott Simpson fired a 68 for a 143 total, joining fellow American David Ishii at that figure. Ishii had a 72 Friday.

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ICHIHARA, Japan (AP) - Tu Ai-yu of Taiwan fired a 4-under-par 68 Friday and took a one-stroke lead after the opening round of the Fijitsu Ladies Golf Tournament.

Tu one-putted eight holes on the 6,347-yard, par-72 Hamano Golf Club course.

''It's my first 60s in many weeks, and I'm glad I was putting pretty well today,'' Tu said.

Rookie Chieko Nishida, who won her first tournament last week at the Takara Invitational, shot a 69 and tied for second with Chikayo Yamazaki, winner of three tournaments this year.

Another stroke back at 70 were defending champion Amy Benz of the United States and four others, including Nayoko Yoshikawa, Mayumi Hirase, Ritsu Imahori and Kumiko Hiyoshi.

Hiromi Kobayashi, a regular on the LPGA Tour, shot a 72.

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ST. ANDREWS, Scotland (AP) - An increase of up to 25 percent in prize money and three new tournaments highlight the 1991 PGA European Tour, which will start in the Middle East if political developments allow.

Ken Schofield, the tour's executive director, said Friday that purses would increase by at least 16.6 percent, to $36.58 million and could get as high as $38 million, compared to $31.35 million this season.

The Tour is scheduled to start Feb. 7-10 in Dubai, United Arab Emirates. Political developments in the Gulf region could change that, but officials are proceeding on the assumption that a solution to the confrontation over Iraq's invasion of Kuwait will be found by then.

''This is a problem for us,'' Schofield said. ''We had a word with the people in Dubai and told them that if they wanted to skip it in 1991, people would understand. But they said no, they feel it will be resolved by February.''

New tournaments are the Barcelona Open on Feb. 21-24; Catalan Open in Tarragona, Spain, on March 14-17, and the Jersey Open in La Moye on April 11-14, the same dates as the Masters.

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GENOA, Italy (AP) - Genoa's police chief apologized Friday for the rough treatment of Sampdoria fans in Marassi stadium during Wednesday's first-round final of the European Super Cup.

Attilio Musca said that the intervention of riot policemen was touched off by ''a misunderstanding'' - a minor scuffle between two fans.

Fourteen Sampdoria fans and 12 policemen were injured, none seriously, in violent clashes during the second half of the Sampdoria-AC Milan match which ended in a 1-1 tie.

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LONDON (AP) - British Formula One driver Martin Donnelly is responding slowly to treatment but remains unconscious with injuries suffered in a crash during practice for the Spanish Grand Prix two weeks ago.

Although he still requires kidney dialysis, Donnelly is breathing without the help of a ventilator, Janet McKenzie of the Camel-Lotus team said Friday.

Doctors have stopped sedating Donnelly, who is from Northern Ireland, and say he should regain consciousness, McKenzie said.

Donnelly's fiancee, Diane McWhirter, said his family were heartened by a specialist's report on Donnelly's legs, both of which were broken.

''They reported that the joints look OK and all the bones are in line and should heal,'' she said.