Atlanta Braves general manager John Coppolella resigned from his position effective immediately following a breach of Major League Baseball rules regarding the international player market, the team announced Monday.
"Major League Baseball is investigating the matter with our full cooperation and support," John Hart, the Braves' president of baseball operations, said in a statement. "We will not be issuing any further comment until the investigation is complete."
The Braves will begin an immediate search for Coppolella's replacement and Hart will perform the GM duties until a replacement is named, the team announced.
Yahoo Sports reported that MLB discovered the breach of international signing rules as part of a much larger investigation of the Braves and Coppolella, including Atlanta's domestic draft practices and Coppolella's treatment of team employees.
Coppolella, 38, served as the Braves' GM for the past two seasons after being named to the position on Oct. 1, 2015, signing a four-year contract.
Hart and Coppolella were installed atop the Braves' operations department following the September 2014 dismissal of Frank Wren as general manager. Coppolella served under Wren and kept an assistant GM title for one year under Hart before being promoted.
Coppolella oversaw the rebuilding of the Braves' farm system through the domestic draft, the international signing period and a series of trades involving high-profile veterans.
The organization's farm system has improved from bottom-tier status a few years ago to No. 1 or No. 2 according to most experts, the Atlanta Journal-Constitution reported.
The Braves (72-90) just finished their third consecutive 90-loss season.