Big leaguers are getting a reminder that smokeless tobacco is banned this season at stadiums in Boston, Los Angeles and San Francisco.

One-page letters are being put in clubhouse lockers at spring training. The notices come jointly from Major League Baseball and the players' union.

Local ordinances will prohibit smokeless tobacco from Fenway Park, Dodger Stadium and AT&T Park this year. There is similar legislation being considered in New York City, and both the Mets and Yankees say they support such a ban.

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Smokeless tobacco isn't permitted throughout the minor leagues. There is no outright ban on dipping in the majors, and the issue is certain to be discussed in upcoming labor talks between MLB and the union.