Steiner, a hard-hitting third baseman, played for St. Louis University from 1970-73. In 1973, he set the Billiken record for most hits in one game with five, then tied his own record two weeks later with a five-hit game against the University of Missouri. Steiner was also a pitcher during his senior year at SLU, posting a 3-0 record and 2.42 ERA.

He played shortstop for St. Louis University High School in the late 1960s.

From 1973-75, he was an infielder and pitcher for American National in the St. Louis County League. Steiner played 17 years in the St. Louis Men’s Senior Baseball League. During the last four years, he pled in both the Over-35 division and the Over-45 division. From 1994-2004, he toiled for Sports Print in the MSBL Over-35 division. From 2005-2010, he played for the Over-35 Bandits, helping his team win league championships in 2005, 2006 and 2007. From 2007-10, he was with the Over-45 Bandits. He played in four Fall Classic National tournaments in Florida. He was selected to the MSBL all-star team twice. In 2007, he batted .474 at the age of 56.

Steiner was a CYC baseball coach in the St. Louis area for many years.