Plummer was born in Oakland, California and attended Anderson Union High School in Anderson, California. He was signed by the St. Louis Cardinals on April 25, 1965, as an amateur free agent. Plummer played three years in the Cardinals' minor league system, then was drafted by the Cubs on November 28, 1967, in the Rule 5 Draft. Plummer spent nearly all of 1968 on the bench and catching in the bullpen in Chicago due to the rules on sending Rule 5 drafted players to the minor leagues. Plummer made his major league debut with the Cubs on April 19, 1968 at the age of 21 in a road loss to the Cardinals. Pinch-hitting for Chuck Hartenstein, he struck out against Hal Gilson. He had only one more at-bat that season and played in just two games. Traded to the Reds for Ted Abernathy on January 9, 1969, Plummer spent the year at Triple-AIndianapolis. He was in the minors again in 1970, but was called up to the pennant-winning Reds in September, long enough to play in four games with nine plate appearances, including his first career hit. While never a regular starter—he was Johnny Bench's backup catcher during the Big Red Machine years—he did play solid defense with a.983 fielding percentage, but was a lifetime.188 hitter. His most memorable game was in 1974, when he hit two home runs in Philadelphia off hall of famerSteve Carlton. Plummer's career as a backup catcher was profiled in a Sports Illustrated article in July 1977. "I've always wondered how Bill would do if he played two months straight," said Pete Rose. "He's a physical fitness nut, and if hard work means anything, he would do all right." The article's writer said of Plummer, "He is a private person. He hoards his time and spends it with his wife Robin and two daughters, Gina and Tricia. He doesn't drink, works out, jogs and plays tennis, and during the winter he labors on his father-in-law's northern California cattle ranch. In Summer 2020, a documentary entitled Plum: A Life in Baseball, about Plummer's 53-year baseball career, will be released.
Coaching
After he retired as a player, Plummer stayed in the Mariners' system, and managed the Wausau Timbers in 1981, and the Triple-A Calgary Cannons from 1986 through 1988. He was the Mariners' third base coach starting in 1989, and when third-year to manager Jim Lefebvre was fired after the 1991 season, the franchise's first with a winning Plummer was promoted for 1992. Seattle finished in last place in his only season as manager, with a record, and Plummer was let go in October. The club had been sold in July, and he was succeeded in November by Lou Piniella for the 1993 season. Plummer spent 1993 and 1994 in the Colorado Rockies organization, starting the 1993 season as the AZL Rockiespitching coach and ending the season as the major league bullpen coach in Denver. In 1995 Plummer returned to managing with the Jacksonville Suns, the Detroit Tigers Double-A affiliate. In the spring of 1996, the International Division of Major League Baseball sent Plummer and other coaches, including Fernando Arroyo, Jim Lefebvre, and Greg Riddoch to serve as official advisors to the upstart Taiwan Major League. In 1996, Plummer would convert Tigers third baseman Phil Nevin into a catcher in Jacksonville. The Tigers fired Plummer from Jacksonville at the All Star Break, despite winning the Southern League first half championship and Plummer would the season managing Cincinnati'sBillings Mustangs. Plummer went on to manage independent league baseball with the Western Baseball League's Chico Heat from 1997–1999, and Yuma Bullfrogs from 2000-2001. In 2002, he joined the Arizona Diamondbacks' minor-league system, eventually working his way up to their Triple-A affiliate, the Tucson Sidewinders, which he managed in 2007-2008. Plummer managed the Tigres de Aragua for the 2001-02 season. Plummer served as the minor league catching coordinator for the Diamondbacks from 2009 to 2012. He managed the Naranjeros de Hermosillo of the Mexican Pacific League for parts of the 2011-12 and 2012-13 seasons, taking them to the playoffs in 2011-12. Plummer managed the Leones del Caracas to a Venezuelan Winter League championship in 1986-87. He also managed Caracas for the 1988-89 season. In 2013, he served as manager of the Diamondbacks' Single-A affiliate Visalia Rawhide of the California League in his 22nd season as a minor league coach or manager. Through the 2013 season, he had a career minor league managing record of. In 2014, Plummer reassumed the role of Arizona Diamondbacks catching coordinator. Plummer announced his retirement at the end of the 2017 season, with a career managerial record of Since 2018, Plummer worked as the hitting and catching coach for the summer collegiate Redding Colt 45s.
