Kenneth Leo Retzer
- Bats Left, Throws Right
- Height 6' 0", Weight 185 lb.
- School Jefferson City Junior College, Central Missouri State University
- High School Wellsville (MO) High School
- Debut September 9, 1961
- Final Game October 3, 1964
- Born April 30, 1934 in Wood River, IL USA
- Died May 17, 2020 in Sun City, AZ USA
Retzer was born in Wood River, IL, across the river from St. Louis, MO. He signed as a free agent with the Cleveland Indians in 1954. He hit over .300 in both 1954 and 1955, and usually hit over .275 as he moved up the minors. He missed the 1957 season while serving in the United States Army.
After spending years in the minors, he made his major league debut in September 1961. He had spent most of 1961 with the San Diego Padres. In his first stint with the Senators, Ken hit .340 in 53 at-bats. Gene Green was the Senators' regular catcher in 1961.
Ken became the regular in 1962, with Green having been traded to the Cleveland Indians. In 1962, Ken hit .285 and slugged .400. The team batting average that year was .250. Ken was again the regular in 1963, and while his batting average dropped to .242, the team batting average was only .227.
In 1965 Ken played for the Denver Bears and in 1966 for the Oklahoma City 89ers. He was 32 in 1966, the same age as Jim Gentile, his teammate at Oklahoma City. In 1967 Ken split his time between the Rochester Red Wings and Portland Beavers. His manager at Rochester was Earl Weaver, at the time a veteran minor league manager who would start on a major league managing career the next season.