The possibility of a player boycott of the 1985 All-Star Game has been introduced as management and labor continue what the union calls an "absurd" line of negotiations toward a new baseball contract.

Management's negotiating team, led by Lee MacPhail, supplied the union further details in New York yesterday of its earlier proposal to place a salary cap on all major league teams. Limitations would primarily affect signing of free agents.

"As they filled in the details, the proposal, which was absurd to start with, has become even more absurd," said Marvin Miller, former executive director now a consultant to the Major League Players Association.

New York Yankee Don Baylor, American League player representative, meanwhile had started a flap by saying: "If the players want to walk out on the All-Star Game and resume playing later, that's become a genuine possibility. I'd say that the All-Star Game is in jeopardy."

Don Fehr, Miller's acting successor currently making rounds to sound out the players, said from St. Louis that a boycott of the All-Star Game, July 16 in Minneapolis, is a possibility -- "We haven't foreclosed any of the options."

"There is no contractual obligation ever for a player to play in an All-Star Game," Miller said. "You could refuse to play in that game without engaging in a strike. There is nothing in a player's contract or in the Basic Agreement that requires players to play in the All-Star Game." . . .

Cincinnati player-manager Pete Rose might have passed Ty Cobb's 4,191 hits by now but for 63 games lost to strikes in 1972 and 1981. Yet he said he would vote for a strike (Fehr was to poll the Reds in St. Louis) as he closes in now on Cobb. "You would, too," said Rose, "if you knew the facts." . . .

Atlanta Manager Eddie Haas got owner Ted Turner's vote of confidence after team officials met to discuss the Braves' dismal 1985 record.

"Considering . . . pitching problems, some caused by injuries . . . and that we haven't scored a lot of runs in key situations, we think Eddie Haas has done a fine job," said Turner, just back from Russia. "He has our complete support and backing."