Washington Nationals vice president Bob Boone has informed the team that he will resign instead of complying with a COVID-19 vaccine mandate for all non-uniformed employees, a source confirmed to ESPN on Wednesday.

Boone, 73, has been with the organization since 2005 and serves as a senior adviser to general manager Mike Rizzo. Boone was assistant GM and vice president of player development from 2006 to 2013.

News of Boone's resignation was first reported by The Washington Post.

Boone was a star catcher for the Phillies, Angels and Royals from 1972 to 1990 and also managed the Royals and Reds between 1995 and 2003. He is the father of New York Yankees manager Aaron Boone and former MLB infielder Bret Boone.

Aaron Boone announced in March that he was vaccinated against COVID-19.

In addition to the resignation of Boone, two scouts will not be with the Nationals organization next season due to the vaccine policy, according to a report by The Athletic.

The Nationals were one of the first teams in baseball to require vaccines for non-playing, full-time employees, including coaches, executives and staff. The policy went into effect Aug. 12 and employees needed to meet an Aug. 26 deadline to provide proof of first shot or apply for an exemption.

"As a company, we have a responsibility to do everything we can to keep one another safe and felt that mandating vaccines was the absolute right thing to do for our employees and our community," the Nationals said in a statement on Friday.