Baseball rules corner: umpires have to be especially careful when calling foul balls.

DOES BASEBALL HAVE A NO HARM, no foul policy?

Take what happened during a game at Oakland where the A's hosted the Mariners last July 3.

The A's were batting in the fourth inning with two on and two out when Eric Byrnes grounded out harmlessly to first baseman Greg Colbruun. But first base umpire Greg Gibson called a foul ball immediately after Byrnes made contact. Gibson thought Byrnes had hit the ball off his front foot, thus making it foul.

Knowing the ball was in play, Byrnes took off for first on the crack of the bat apparently not aware that Gibson had ruled the play a foul ball. According to writer Mitch Stephens of the Seattle Post-Intelligencer Byrnes slowed down after noticing Gibson's call

Seattle skipper Bob Melvin argued the ball never hit Byrnes' foot. Three of the four umpires agreed.

The crew met near the pitcher's mound for a couple of minutes and decided to call Byrnes out, but first called upon Oakland manager Ken Macha, who after a long, heated discussion protested the game.

At that point, crew chief Dana Demuth signaled Byrnes out, drawing thunderous boos from the 19,612 in attendance.