Happy New Year, and . . .

Marvin Miller suddenly has flashed a joker in the deck known as the basic agreement between the major league clubs and his players association, one that could make Fred Lynn, Carlton Fisk, Rick Burleson and John Mayberry free agents before the 1981 baseball season.

In the relief over the strike-averting agreement reached May 23, everybody overlooked, or misinterpreted (if Miller's interpretation is correct), a ramification of a clause that allows a player with six or more years in the majors and not eligible to be a free agent to ask his team, between Jan. 15 and 25, for binding salary arbitration, conducted in February. If the club refuses, says Miller, the player becomes a free agent right then.

Lynn and Fisk are Boston property, as was Burleson until his recent trade to California; Mayberry is with Toronto. The Red Sox front office says it assumed the fact Lynn and Fisk were going into their option years meant they were still under contract; Miller says not so. "All the option does is give the team the right, if they cannot come to an agreement on a new contract by March 1, to renew that contract for one more year . . . If the club doesn't exercise the option, where is the contract?"

And where is, say, Lynn if the Sox -- who had expected to pay him $275,000 for 1981 -- don't wish to risk shelling out the $1 million he presumably would demand for a final one-year stand and quite possibly win (what with current superstar rates) from the arbitrator?