Jonathan Papelbon. (Jonathan Newton / The Washington Post)

NASHVILLE — Washington Nationals closer Jonathan Papelbon filed a grievance against the organization shortly after he received a team-issued unpaid suspension for his role in a dugout fight with star outfielder Bryce Harper in September, according to a person familiar with the situation. The grievance, which was first reported by Boston radio station WEEI, adds another layer of friction to the strained relationship between Papelbon and his employer.

A hearing for the case has not yet been scheduled but is expected to take place before the start of the 2016 season.

Acquired by the Nationals before the July 31 trade deadline, Papelbon was suspended four games without pay after he grabbed Harper by the throat on Sept. 27. When that ban was coupled with his three-game suspension from Major League Baseball for an unrelated incident with Baltimore Orioles infielder Manny Machado, Papelbon missed the rest of the season. But the team-issued suspension cost him about $284,000 of his $13 million 2015 salary.

The person familiar with the situation said the main argument of Papelbon’s camp is that there is no precedent for a team-issued suspension over such an incident.

Nationals General Manager Mike Rizzo will address the situation on Monday during his scheduled meeting with reporters at the MLB winter meetings in Nashville.

According to the collectively bargained rules between MLB and the players’ union, players can be disciplined for just cause for conduct that is “materially detrimental or materially prejudicial to the best interests of baseball including, but not limited to, engaging in conduct in violation of federal, state or local law.” MLB and a team cannot both suspend a player for the same issue.

The rule also reads: “In cases of this type, a Club may only discipline a Player, or take other adverse action against him, when the Commissioner defers the disciplinary decision to the Club.” But a player also has the means to dispute a suspension through a grievance, too.

When Papelbon’s suspension was issued on Sept. 28, Rizzo was asked if the players’ union had any involvement. He said: “My job isn’t to dole out discipline, in regards to what the players’ association is going to do. We felt it was important enough to make a statement that you’re suspended for four games. What the players’ association does with that information is up for them.”

Rizzo also said he was in contact with Papelbon after the suspension was decided, they talked about the incident and “we parted amicably, and I left it with ‘We will see him shortly after the season.’ ” But that wasn’t exactly how Papelbon felt.

Papelbon seems like a likely trade candidate because of what happened this season. He posted a 3.04 ERA and saved seven games in 22 appearances with the Nationals but struggled some down the stretch and then was suspended for the final seven games. He is owed $11 million in 2016 and, given his checkered past, could be difficult to trade. Papelbon and Harper have talked since the incident. And the Nationals believe they can hold on to both Papelbon and Drew Storen next season, but it remains to be seen whether they will.