The Dacor Taste of Tennis is an annual charity event that pairs tennis stars in town for the U.S. Open with famous chefs while they prepare dinner — nowhere else can you see, for example, 2001 Open champion Lleyton Hewitt, aproned, serving braised beef short ribs — and, conveniently, presents a chance to see players like Andy Roddick and Rafael Nadal up close without having to schlep to Queens. Roddick, in fact, figured in the main event last night: He cooked up a mango delicacy with Aquavit chef Marcus Samuelsson while the cameras captured his innocent look and eternal stubble. We asked German Nicolas Kiefer what his favorite pre-match meal is and reflected on his native cuisine. “If I have a Wienerschnitzel, I think I would score pretty low,” he said. Beyond that, and partly because only CBS was allowed to question Messrs. Roddick and Nadal, we turned to an unlikely source for insight on the impending contest: the D.J., one Mad Linx, who hosts BET’s Rap City and is, apparently, a tennis fanatic. Linxx predicted a victory for favorite Roger Federer. “Federer will go down as the best ever,” he said. “He will probably win twenty Grand Slam tournaments before he retires.” Not the evening's star, Roddick? “Roddick has nightmares about Federer,” the D.J. insisted. “Nightmares.” —Marc Tracy