In 1914, when Jack Dunn, manager of the minor league Baltimore Orioles, was shopping his prize prospect Babe Ruth around the major leagues, he failed to contact his former teammate, Giants manager John McGraw. McGraw was so upset by the snub that over a decade later, he refused to negotiate with Dunn about another big prospect. As a result, Dunn ended up selling future Hall of Famer Lefty Grove to Connie Mack of the Philadelphia Athletics.

Grove of course went on to win 300 games for the A’s and Red Sox, an MVP award in 1931, and was selected six times as an All-Star. He is considered one of the all-time greatest left-handed pitchers.

Thou should not hold grudges when it come to player transactions.