With a little more than six months before the expiration of baseball’s collective bargaining agreement, negotiations have a new but not unexpected wrinkle: a grievance worth roughly half a billion dollars.

About two weeks ago, the Major League Baseball Players Association filed a grievance worth an estimated $500 million alleging MLB did not act in good faith when it set a schedule for the pandemic-shortened 2020 season, people with knowledge of the grievances said. The union believes the league chose to play fewer games than it could have and thereby unduly reduced player salaries. In a one-off arrangement, the league and the union agreed to tie player salaries during 2020 to the number of games played.

MLB met that grievance with a counter-claim arguing, in part, that the final number of games, 60, was a necessary maximum for health and safety reasons. The union’s grievance does not specify an exact number of games it believes the league should have played, a source said, but the $500 million amounts to somewhere in the vicinity of 20 days of league-wide pay at an estimated clip of $25 million per day.

Both the league and the union declined to comment. It was well known that the union was planning to file the grievance, but the grievance’s formal submission was not publicly known until a New York Post report Thursday.

The manner in which the grievances will be resolved, their full substance and the timing of the process is, for now, unclear.

MLB has asked the union to expedite the grievances so that they can be resolved as soon as possible in advance of the CBA’s expiration on Dec. 1. The union might be amenable to moving quickly, but also could be leery of a process that does not include sufficient discovery or production of relevant information. The case, particularly if it goes to a hearing, could be lengthy and complicated. Players might also want the case to be fast-tracked if it means they could see additional cash.

But a hearing isn’t the only way to resolve the issues. The parties could mutually agree to settle during collective bargaining, where both parties now have new forms of leverage. The union could dangle a willingness to drop the claim as an incentive for MLB to meet certain demands for the next CBA — an outcome that has the potential to be more valuable to the players than a straight cash award. The union likely would take issue with a suggestion that the grievance is merely a bargaining tactic, however.