Christopher Michael Russo (born October 18, 1959), known as "Mad Dog," is an American sports radio personality best known as the former co-host of the widely popular Mike and the Mad Dog sports radio show with Mike Francesa, which was broadcast on WFAN in New York City and simulcast on the YES Network. Russo joined Sirius XM Radio in August 2008 and is in charge of his own channel, Mad Dog Radio. He also hosts an afternoon radio show, Mad Dog Unleashed, that is the lead program of Mad Dog Radio.