USA Today’s Michael McCarthy on the growing trend of sneaker companies lavishing endorsement deals on hip hop artists that might’ve otherwise gone to professional athletes.

Rap stars provide a “street credibility” that many sports stars lack, says Bob Dorfman who rates the endorsement potential of current athletes.

“Jay-Z’s shoe is more successful than that of most athletes,” says Dorfman, creative director at Pickett Advertising in San Francisco. “Look at (NBA Finals MVP) Tim Duncan. He’s a superstar, but he’s boring. He’s not American. He doesn’t have credibility on the street.”

Duncan, a native of St. Croix, is very much a U.S. Citizen by birth. He also represented his country in the last Olmpic Games (admittedly something that won’t help his Q rating). Duncan’s lack of pizzaz is continually cited, but there isn’t a GM in the NBA who wouldn’t kill to have a player like him. I don’t doubt that Duncan is a tough sell, though perhaps a campaign that pokes fun at his dull image is in order (McDonalds worked wonders with Alan Shearer, a guy so wooden and expressionless, he makes Duncan look like Liberace by comparison). I don’t know what Dorfman’s credentials are to be lecturing about street cred, but at least he isn’t teaching high school geography.