The door is wide open for a mass exodus of America's big-name swimmers from college programs because of a new NCAA rule that drastically changes the way athletes train, shaken college coaches say.

"Isn't it sad that someone who is as excellent a student as Janet Evans has to quit college to pursue her dream," Texas women's coach Mark Schubert said at the U.S. Spring Nationals meet Thursday. "I think it borders on criminal."Evans, winner of three gold medals at the Seoul Olympics three years ago and holder of three world records, dropped a bombshell when she announced she was going to give up her final two years of eligibility at Stanford.

NCAA officials said Thursday that its new rule is being misinterpreted. They said Evans and other world class swimmers can still get in as much supervised pool time as they like.

College swimming programs are waiting for more big names to follow Evans, however. Evans said the NCAA should reconsider its rule before it's too late.

Evans and Tennessee's Melvin Stewart, also a world record holder, said Wednesday they were leaving school to better prepare for the 1992 Olympics. Both are competing here.

Each blamed the new NCAA rule, which takes effect in August. They said it cuts a world class swimmer's supervised workout schedule, which usually averages 35 to 40 hours a week.

But while college swimming officials criticized the new rule, the NCAA said the 20-hour rule is being misintrepreted.

Said Jim Marchiony, NCAA director of public relations: "That limit refers to the amount of time that a coach can require a student athlete to participate in his or her sport. Swimmers can voluntarily practice as many hours as they want."

Ted Tow, the NCAA's associate athletic director, said he wasn't surprised that Evans and Stewart decided to leave school.

"It's not the function of college athletics to prepare world class athletes," said Tow, in San Diego for the NCAA President's Commission meetings. "The function of collegiate athletics is just that - to function within the constraint of academics. You'll always find some outstanding athletes who choose not to function within the official framework."