The Chicago White Sox are mandating COVID-19 booster shots for all minor league players, telling them in an email Friday that they "will not be able to participate" in spring training without being fully up-to-date on vaccinations, according to a copy of the letter obtained by ESPN.
The White Sox are the first team known to require vaccinations for minor league players. In late January, Major League Baseball told teams that vaccines would not be mandatory for minor league players but would be for managers, coaches and other staff that come into regular contact with players.
In the letter to players, the White Sox said players needed to send "proof of receiving the COVID booster vaccine" and that "you will need to have proof of vaccination before reporting to Spring Training or you will not be able to participate." Players are expected to report to spring training Feb. 21. The White Sox last spring mandated vaccines for minor league players and, according to sources, had 100% compliance.
Because minor league players are not represented by a union, organizations can unilaterally implement rules such as a vaccine mandate. Major league players on teams' 40-man rosters are not subject to a mandate, which would need to be collectively bargained.
The White Sox will not grant releases to minor leaguers who refuse to receive the vaccine, a source told ESPN, confirming a report in The Athletic.
Multiple minor leaguers currently in the White Sox organization are unvaccinated, sources told ESPN, and others have not received the COVID boosters the team is mandating.
In a statement, the team said: "The Chicago White Sox are requiring all of our employees to be up to date on their COVID-19 vaccination status, and this requirement extends to our minor-league players as well. We believe this is the right thing to do to protect the health and well being of all of our players and staff across the organization."