William Ernest Hayes (born October 24, 1957 in Cheverly, Maryland) was a catcher for the Chicago Cubs (1980–81). He attended Indiana State University.
In 2 years, he played in 5 games and had 9 At Bats, 2 Hits, 1 Double, .222 Batting Average, .222 On-base percentage, .333 Slugging Percentage, and 3 Total Bases.
Coached/managed in the minor leagues from 88-97 and 99-02, with a stint coaching in the majors in between. He is now the bullpen catcher for the National League West Division San Francisco Giants. He started bullpen catching with the SF Giants in 2003 after managing in San Jose (SF Giants farm club) in 2002.