RENO, Nev. (AP) _ Scotty Olson of Canada chased a backpedaling Pedro Feliciano of Puerto Rico and outgunned the champion in the clinches before stopping him in the ninth round to take the United States Boxing Association flyweight title.

''Right away, I felt physically stronger,'' Olson said after the referee stopped Sunday night's fight at 1:09 of the ninth. ''I just had to wear him down with my strength.''

Olson, 20-0 with 16 knockouts, assumed command at the start and sent the champion to the canvas in the second round. Feliciano went down again in the fifth and early in the ninth.

Referee Vic Drakulich let the fight resume, then quickly called a halt to the bout as Feliciano wobbled near the ropes. His trainer was entering the ring to stop the fight as Drakulich moved in.

''It may not have been the toughest fight of my life, but it was the biggest,'' said Olson, a member of Canada's 1988 Olympic team. ''I needed this to move on to bigger things.''

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TAURANGA, New Zealand (AP) - French brothers Thierry and Vincent Berger captured their second consecutive victory today to take a commanding lead after five heats of the world Flying Dutchman sailing championships.

New Zealand's Murray Jones and Greg Knowles finished second and are also second overall.

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PROVIDENCE, R.I. (AP) - A four-alarm fire destroyed Rhode Island College's Walsh Gymnasium, the hub of the school's physical education program and the storage facility for virtually all its athletic equipment.

The fire broke out shortly after 2 a.m. Sunday and was under control by 4:30 a.m., Providence Fire Department spokesman Manuel Vierra said. Firemen remained at the scene hours later pumping water on the debris while the city's fire marshal and other investigators searched for the cause.

The building was declared a total loss, but an exact damage estimate was not immediately available. There were no injuries.

The two-story brick building also housed the school's Athletic Department and the Department of Physical Education, Health and Dance. The fire left more than 20 faculty members, including Baird, without offices. Five classrooms, a dance studio and a golf driving range also were lost.

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LONDON (AP) - Irina Sumnikova scored on a drive with four seconds left to give Minsk an 84-82 victory over the University of Tennessee in the final of the World Invitational women's tournament at Crystal Palace.

Sumnikova led all scorers with 24 points in Sunday's game. Peggy Evans led Tennessee with 18 and Dana Johnson added 15.