The Indians put both Mike Clevinger and Zach Plesac on the restricted list due to their violation of team protocols on their road trip in Chicago:

Antonetti said the decision to put them on the restricted list was not mandatory, but the Indians felt it was appropriate given their actions.

“It’s not ideal,” he said. “But we felt it was the right thing to do. We said from the beginning, even if you go back to March 13, we will continue to prioritize the health and wellness of our players and staff. Based upon the behaviors of Zach and Clev, we felt that they had an elevated level of risk, so we wanted to make sure we did what we could do to protect the rest of our group.”

ESPN.com

It’s my opinion that these kinds of violations by the players will hurt the MLBPA if they file a grievance against MLB over the negotiations for length of the season. MLB will point to the Marlins, Cardinals, and these two pitchers and say the owners were right to worry about the season being shortened due to a virus outbreak. Unlike the length of the season, these protocols were negotiated, so maybe MLB might end up filing a grievance of their own.