Donald Robert "Duffy" Dyer (born August 15, 1945 in Dayton, Ohio) is a former MLB catcher. He played for the Mets from 1968 to 1974.
He began his career with the Mets back on September 21,1968. He is a part of the 1969 World Champion Mets team.
In the October of 1974 he was traded to the Pittsburgh Pirates for outfielder Gene Clines.