Steiner is an American sportscaster. From 2002 to 2004, he was an announcer for New York Yankees radio broadcasts, along with co-host John Sterling, but he left after the 2004 season to join the Los Angeles Dodgers alongside Vin Scully, Rick Monday and Steve Lyons, to fill the void left by Ross Porter's departure, and XM Radio's MLB Home Plate, where he hosts Baseball Beat, a daily show featuring baseball writers, columnists and broadcasters.

Apart from his knowledge of baseball, Steiner is also known for his knowledge of boxing, a sport in which he covered some major fights for SportsCenter. He won a CableACE award for a program about Muhammad Ali and a Clarion award for his coverage of the Mike Tyson rape trial.

He was involved in many, often comical, situations during his tenure on ESPN's SportsCenter, including one broadcast when Carl Lewis sang the national anthem at a New Jersey Nets game. Amused by hearing Lewis sing, Steiner simply could not contain himself and began laughing during the SportsCenter show that night, not being able to stop himself until the show ended. His famous comment on the event was that the song had apparently been written by "Francis Scott Off-Key."

Allegedly, Steiner raised some eyebrows with his calling of Cal Ripken Jr.'s last All-Star Game at Safeco Field in 2001, with comments that made some question the legitimacy of Ripken's home run against Dodgers pitcher Chan Ho Park that day. His comments during that game led some to think that Ripken might have been allowed by Park to hit that home run, in order to '"go out in style."' However, the only comment that might be attributed to that end is, "Who wrote this script?", which may have been facetious in nature.

He was featured on one of the most famous SportsCenter television promos from their This is SportsCenter comical promo campaign. In 1999, amid fears of the Y2K situation, Steiner starred in a SportsCenter promo, where SportsCenter cast spoke about a contingency plan at ESPN's studios after Y2K, and Steiner was featured wearing a tie as a head band and screaming the phrase "Follow me to freedom!" He would later scream this phrase at Wrigley Field after singing Take Me Out to the Ballgame on August 31, 2005.

On August 9, 2004, Steiner returned to ESPN to co-host an "old school" version of SportsCenter with Bob Ley.