Career
Pleis, listed at 5 feet 10 inches (178 m) tall and 170 pounds (77 kg), was a relief pitcher for all but ten of his 190 big-league appearances. He appeared in the 1965 World Series against the Los Angeles Dodgers, a team he would serve as a longtime scout after the end of his playing career. Los Angeles went on to prevail in seven games.
Pleis retired from pitching after the 1968 season.
He allowed 269 hits and 127 bases on balls in 280⅔ innings pitched in the Majors, with 184 strikeouts, 13 saves and one complete game.