In 1989, Greenberg graduated from Northwestern University,[3] where he joined the Theta Chi fraternity, and started work as a sports anchor and reporter at WMAQ-AM in Chicago.

He left WMAQ in 1992 to work for WSCR-Radio as a reporter (covering events such as the World Series and the Super Bowl) and talk show host.

In 1995, he left SportsChannel Chicago to work at CLTV, becoming an anchor, reporter, and host of a live call-in show.

He left Chicago in September 1996 for ESPN, where he became one of the first hosts[3] of ESPNEWS when it began broadcasting in November of that year.

Golic would select one of his (presumably) dozens of sheets against Greenberg, with the loser having to perform a humiliating stunt, usually on the air.

Greenberg received advice about milking a cow from ESPN baseball analyst Buster Olney, who grew up on a dairy farm.

On February 20, 2008, Greenberg appeared, along with his radio partner Mike Golic, on the soap opera Guiding Light[9] as reported on ESPNradio.com.

[10] On March 7, 2006, Greenberg released his first book entitled Why My Wife Thinks I'm An Idiot: The Life and Times of a Sportscaster Dad, which reached 14th on the New York Times Bestseller list and was nominated in the 2006 Quill Awards for best sports book.

Along with the release, the two Mikes embarked on a 15-city book tour that included stops in New York City, Philadelphia, Pittsburgh, Chicago, Dallas, Boston, and Tampa.