Last May, the city of San Francisco passed an ordinance that bans players from using smokeless tobacco at AT&T Park.
Thursday night's exhibition game between the A's and Giants is the first game where the law will be in effect.
Throughout spring training, the San Jose Mercury News conducted an anonymous survey of 25 Giants to find out how the players feel about the law.
"I can see it from both sides of the fence," Buster Posey told Andrew Baggarly. "You want to be a good example for children, and we are role models.