William Ernest Hayes
- Bats Right, Throws Right
- Height 6' 0", Weight 195 lb.
- School Indiana State University
- High School St. Patrick High School (North Platte)
- Debut September 30, 1980
- Final Game September 3, 1981
- Born October 24, 1957 in Cheverly, MD USA
After his playing career ended, former catcher Bill Hayes managed in the minors from 1988 to 1997. He was the Colorado Rockies bullpen coach in 1998, and managed in the minors again from 1999 to 2002. Hayes was the San Francisco Giants bullpen catcher from 2003 to 2014. In 2010, he was designated as a special coach and in 2015, he was appointed first base coach, staying on in 2016 as well.
His only major league playing time came in 1980 and 1981 in a handful of games as a catcher for the Chicago Cubs. His 2 career hits came in the same game on October 4, 1980 against the Pittsburgh Pirates. He singled off Pascual Perez and doubled against Kent Tekulve.