A Marvelous Marvin Hagler-Sugar Ray Leonard middleweight championship fight took a major step toward reality yesterday when Leonard's adviser, Michael Trainer, received a call from Hagler's manager suggesting that the two meet "in the very near future" to negotiate a bout.

What's more, Trainer said that Pat Petronelli, Hagler's manager, indicated that they would be discussing a Hagler-Leonard fight for sometime this year, thus putting it ahead of a proposed November rematch of Hagler and Thomas Hearns, whom Hagler knocked out in three rounds last year.

"My feeling would be that they were talking about the fight taking place this year," Trainer said.

"It looks good," he added. "Some things have to be worked out. It's going to take some time. But Marvin wants to fight, obviously. Ray wants to fight. I'm going to meet with Pat in the very near future -- a week or 10 days. Everything is on the right course."

What Trainer has called "the first stage" in preparing for a Hagler-Leonard fight has been achieved -- assuring Hagler that Leonard is serious in his challenge to come out of retirement to meet the middleweight champion, and ascertaining whether Hagler is interested in meeting Leonard.

"There are a lot of things that have to be worked out," Trainer said. "But we're over the first hump. They're interested in it. Marvin's interested in it."

Trainer, who had been waiting for several days to hear from Petronelli, said he thought Hagler "wanted to be sure that everything was for real. Now, he's convinced it is."

Petronelli, who was not available for comment yesterday, said last week that Hagler wanted to fight Leonard before meeting Hearns. "There are some complications, but nothing that can't be worked out," Petronelli said.

Trainer said yesterday that Hagler and Petronelli have "wanted to be absolutely sure they're not committed to anything meaning a rematch with Hearns , which they've indicated they're not."

A Hagler bout with Leonard, the former welterweight champion who has fought only once since November 1982, could produce the largest boxing payday in history.