NEW YORK -- In the midst of difficult negotiations for a new collective bargaining agreement, Major League Baseball and its players' association are scheduled to start a grievance hearing next Monday over the union's claim the 2020 pandemic-affected season was too short, The Associated Press reported.

Martin F. Scheinman, who took over as baseball's impartial arbitrator after the clubs fired Mark L. Irvings, will hear the case over the coronavirus-impacted 2020 season. If the union prevails, MLB might be liable for hundreds of millions of dollars in damages.

The hearing takes place as the sides are negotiating to replace the labor contract that expires Dec. 1. The sides are far apart in their central proposals thus far, and a lockout starting in December or on the eve of spring training in February appears possible. That would be the sport's ninth work stoppage but first since the 7½-month strike that wiped out the 1994 World Series.

MLB suspended spring training on March 13 last year because of the coronavirus pandemic. Management and the union agreed March 26 "that each of the parties shall work in good faith to as soon as is practicable commence, play and complete the fullest 2020 championship season and post-season that is economically feasible, consistent with" several provisions.

Those provisions stated that without MLB's consent, the season would not start until there were no legal restrictions on playing in front of fans at the 30 regular-season ballparks, no relevant travel restrictions and no health or safety risk to players, staff or spectators to playing in the 30 regular ballparks. The agreement also said the sides "will discuss in good faith the economic feasibility of playing games in the absence of spectators or at appropriate substitute neutral sites."

Starting in late May 2020, the sides spent about a month exchanging economic proposals and virus protocols. MLB started with a plan for each team to play an 82-game season and a sliding scale lowering 2020 salaries from about $4 billion to approximately $1.2 billion. Players countered with a 114-game schedule and about $2.8 billion in salaries.

After a meeting between MLB commissioner Rob Manfred and union head Tony Clark, the last version of the deal proposed by MLB was rejected by the union's executive board in a 33-5 vote on June 22.

MLB then said it intended to proceed with the season under the terms of the March 26 agreement, and two days later it issued a schedule calling for each team to play 60 games in a season that started July 23, down from the 162-game season that had been set to start March 26.

The entire regular season was played without fans. About 11,000 fans per game attended the National League Championship Series and World Series, both played at the neutral site in Arlington, Texas.

Base salaries were reduced to 60/162 due the shortened schedule, and base wages for 40-man rosters dropped from $3.99 billion in 2019 to $1.54 billion in 2020, according to information sent from MLB to teams and obtained by the AP.

The union contends that MLB did not schedule the fullest season economically feasible.

The Associated Press contributed to this report.