VOLLEYBALL

Oscar “Digger” Graybill announced his resignation as UC San Diego’s men’s volleyball coach after seven seasons. Graybill, also an English teacher at Hoover High the past 17 years, will teach English and coach the girls’ volleyball team at Walla Walla (Wash.) High this fall. The Tritons went 75-101 and captured Pacific Coast Volleyball Conference championships in 1989 and ’90 under Graybill. UCSD officials say they will conduct a national search for a replacement.

WOMEN’S TENNIS

Monica Seles, the world’s top-ranked player, will play the Mazda Tennis Classic at the La Costa Resort in Carlsbad, tournament officials announced. Seles, who withdrew from Wimbledon last week because of an injury, told officials she would resume playing in two weeks. The Mazda Classic begins July 29.

GOLF

Jim Myers of Oceanside shot par 72 at the 6,791-yard Pebble Beach Golf Links and is tied for second after the first round of the California Golf Assn. Amateur Championships. Myers, tied with Bryan Pemberton of Pleasanton, is two strokes behind leader Sandy Galbraith of Fountain Valley. Pat Duncan of Rancho Santa Fe shot a 75 at Spyglass Hill to trail by five strokes.

SYNCHRONIZED SWIMMING

The San Diego Sweetwater Dolphins placed fifth in the 11-12-year-old girls National Age-Group Competition in Fairfax, Va. Annie Harris placed sixth in compulsory figures and Jenni Mascari, Anna Mercer and Lindsey Wigginton were sixth in the trio competition for the Dolphins.

SURFING

Three UC San Diego surfers won their quarterfinal heats and advanced in the National Scholastic Surfing Assn. National Championships at Oceanside Pier. UCSD’s ‘A’ (162 points) team was in second place behind UC Santa Barbara ‘A’ (188) in the college division, while Point Loma Nazarene was third and San Diego State fourth.

The UCSD victories were scored by Evan Slater in the men’s competition, Chris Jenkins in the women’s competition and Chris Fessenden in bodyboarding. Carlsbad (62 points), the only San Diego entry, was second behind Huntington Beach ‘A’ after the high school boys’ quarterfinals.