ALL DAY last Friday fans called in to WFAN in New York City, the granddaddy of the nation's all-sports radio stations, to lament the departure of Chris Russo, the Mad Dog half of the wildly successful Mike and the Mad Dog show. The program, which ran from 1 to 6:30 p.m. on weekdays, had achieved exceptional ratings during its 19-year run and distraught callers likened the split of the wacky Russo and the more measured Mike Francesa to the breakups of Abbott and Costello, Martin and Lewis, and even the Beatles.

While the comparisons are farfetched—off, you might say, by an order of magnitude—Mike and the Mad Dog may be the most famous sports radio talk show ever and it cut across societal strata in the U.S.'s largest media market. Just as Angelo from Queens phoned in to reminisce on Friday (his was one of several calls that ended in tears), so did New York governor David Paterson. Over the years calls from regulars like Bruce from Bayside would be followed by a check-in from, say, Rudy (Giuliani) from Manhattan.

The success of Mike and the Mad Dog lay not so much in what was said—Russo, especially, tossed off assertions with scant support—as in how it was delivered. There were rants, usually by Russo, in keening monologues that left him sounding like a hungry, overwrought eight-year-old. And there were stolid opinions, advanced by the sometimes condescending Francesa, whose cadence was part subway conductor, part wise guy, pure New Yorkah. (Mad Dog, to Mike, was always "Dawg.")

Yet the show hooked a varied audience (the novelist Philip Roth reportedly can do spot-on imitations of both hosts) because it had neither the head-to-head stridency (think PTI) nor the sanctimony (The Sports Reporters) that afflicts much of today's on-air sports discourse (that is, barking). These were just two guys talking sports. To tune in to Tony Kornheiser and Michael Wilbon is to watch an increasingly slick, often self-conscious performance. Listening to Mike and Chris felt like eavesdropping.

It was Russo's decision to leave ("Did he get tired of me?... Yeah, maybe he did," said Francesa), and he's reportedly close to a five-year, $15 million deal with Sirius. Francesa will shop for others to work with and has talked of holding an audition at a New Jersey bar. Francesa knows it won't be hard to find someone who understands sports well enough to hammer the big issues. The trick will be to find someone who knows how to talk when he talks about sports.

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