He played from 1962 to 1974 for the Washington Senators, Los Angeles Dodgers, New York Yankees, Seattle Pilots / Milwaukee Brewers, and Boston Red Sox.

He hit a home run in his first major league at bat (on September 5, 1962, against Dick Stigman of the Minnesota Twins), and garnered headlines because both his name and birthdate, May 29, were shared with the President of the United States at the time, John F. Kennedy, born 24 years earlier.

[2] After the 1964 season, he was traded with pitcher Claude Osteen and cash to the Los Angeles Dodgers for five players, including outfielder Frank Howard.

[2] With the Dodgers, Kennedy would be part of history when he replaced Jim Gilliam at third base in the eighth inning of Sandy Koufax's perfect game on September 9, 1965.

Kennedy did not get to bat in that game, nor did he have a fielding chance as Koufax struck out the last six Chicago Cubs he faced to complete his then-record fourth no-hitter.