A knuckleball pitcher, the Missouri native got brief call-ups with the Cardinals in 1952 and 1955. He languished in the Detroit faem system before being dealt to Cleveland where he pitched in six games. Purchased back by St. Louis, he pitched in three games for them in 1961. After the season, he was sold to the expansion Colt .45s.

In that inaugural season, Tiefenauer (pron: TEE-fen-ow-er) appeared in 43 games, notching a 2-4 record with one save and a 4.34 ERA. He kicked around with the Braves, Yankees, Indians and the Cubs afterwards to complete a 10-year career in the majors. He compiled a 9-25 record with 23 saves and a 3.84 ERA.

He spent two decades as a coach in the Phillies organization after his playing days ended. On June 13, 2000, Tiefenauer passed away in his hometown of Desloge, MO at the age of 69. No cause of death was reported.