PHILADELPHIA (Bottom of the Fourth) - Roy Halladay is not used to being penalized for an illegal pitching motion, being one of the most consistent and fastest-working pitchers in the game. So when the Phillies ace was called for a balk in a game Monday night against the St. Louis Cardinals, he was taken aback. So taken aback, in fact, that he balked at the call. This sudden change in demeanour for Halladay was enough to make home plate umpire Jim Davidson balk in turn. "Halladay is like a robot," commented Davidson, "he never breaks rhythm. So when he balked at my balk call, it caused me to balk involuntarily."