The Senior Professional Baseball Association suspended operations yesterday after the two groups that own the Fort Myers Sun Sox were unable to agree on the future of the franchise.

Mark Morley, co-owner of the St. Petersburg Pelicans, said the remaining five league teams had decided they could not continue without Fort Myers. The league was scheduled to begin the second half today, after a holiday break.

Besides Fort Myers and St. Petersburg, teams operated in Daytona Beach, Fla.; Sun City, Ariz., and San Bernadino, Calif. A sixth franchise, the Florida Tropics, operated as a traveling team.

"This has been going back and forth for three weeks," Morley said. "They've been doing as good as anybody, with a really good lease deal, but they just couldn't agree. It was more a matter of principle than anything financial."

Michael Graham is president of the Sun Sox and owns 50 percent of the team. The other 50 percent is owned by J. Simpson Dean and William Curry, both of Wilmington, Del.

This was the second year of operation of the league for players 34 and older. Last season, all teams were required to post letters of credit. When Phil Breen, owner of the Orlando team, was indicted for embezzlement and disappeared, the league kept the team operating with the letter of credit.

"We screwed up when we didn't require letters of credit this year," Morley said. "This is a step backward. We plan to resume next year, but we'll have trouble getting another TV deal after this fiasco." . . .

Nolan Ryan, the 43-year-old who pitched his record sixth no-hitter in 1990 and won his 300th game, has been named the Sporting News man of the year.

Ryan led the American League with 232 strikeouts last season and also pitched his record-tying 12th one-hitter. He got his 300th victory on July 31 as his Texas Rangers beat the Milwaukee Brewers.

Ryan is 302-272 lifetime, with a record 5,308 strikeouts.