Ron compiled some good numbers for his first few years in the minors, and earned a promotion to the Tigers in September 1961. Primarily a starter in the minors, Nischwitz worked out of the bullpen in Detroit. He was with the Tigers for almost all of the 1962 season, in a bullpen featuring stopper Terry Fox and veteran Ron Kline.
After the 1962 season, Ron was traded to the Indians for 3rd baseman Bubba Phillips. Although he played some in Cleveland, Ron spent most of '63 with their AAA team in Jacksonville. 1964 found Nischwitz bouncing around from the Indians' Portland team to the Braves' AAA team in Toronto.
He returned to the Tigers' organization in 1965, splitting his time between Detroit and Syracuse, making his final big-league appearance on September 19th. He wrapped up his career back in Jacksonville in 1966, this time as a Mets' farmhand, pitching in 30 games.
After retirement, Nischwitz coached college baseball for 25 years.