Baseball managment dropped the other shoe today, invoking its controversial compensation proposal for re-entry free agents and advancing the sport's ongoing labor crisis yet another step.

"They have chosen to start the war," said Marvin Miller, executive director of the Players Association. "They have fired the gun."

The long-expected action came in the form of a letter from Ray Grebey, director of the Player Relations Committee, management's bargaining unit, to Miller. It read in part:

". . . Since agreement has not been achieved through negotiations, the 26 major league clubs have chosen to exercise the rights provided and agreed upon in the May 23, 1980 Memorandum of Agreement effective this date, Feb. 19, 1981, to unilaterally adopt and put into effect as part of the basic agreement, the modification in Player Selection Rights. . . "

Management has a right to institute its new system. But it is unlikely the players will accept it.

Managment's plan would provide unprotected roster players as compensation for premium, or as management calls them, "ranking" free agents signing with a new team.

Management's plan involves evaluating players through pitching of batting appearances and the number of teams drafting a player. For compensation to be awarded, a player would have to be drafted by more than eight teams and be in the top half of all players in his league in performance categories. Pitchers would be ranked by appearances and all other playersl by times at bat.

The players have not accepted the idea of compensation in any form. No discussion of compensation criteria has even been attempted.

"You must remember you are dealing with a fraudulent proposal," Miller began. "Their propaganda keeps saying they are interested in compensation for superstars, but that's just not so. If you are making players by plate appearances and saying the top 50 percent qualify for compensation, does that mean the top 50 percent are superstars? That's fraud.

Throughout the talks, management has emphasized that only three players in the 1980 re-entry draft -- Dave Winfield, Don Sutton and Darrell Porter -- would have qualified for compensation under its plan. Miller scoffed at that.

"Do you mean to tell me they're ready to shut down an industry just because they want compensation for three players?" he said.

"What they want to do is stymie free agency for the overwhelming majority of players."

The key word in Grebey's letter was "unilateral." Management had the right to take its action but now the ball is in the player's court. They have until March 1 to decide if they'll seek a strike vote authorization and to announce their intended date (on or before June 1) for a strike. That date would become, in effect, the true deadline for resolution of the compensation problem. The union's executive board will meet next Wednesday in Tampa, Fla., to decide the next step.