Tony Gwynn died at age 54 after battling salivary duct cancer . He 's not the only baseball player to battle oral cancer . MLB changed rules in 2011 but has n't banned tobacco smoking on the field .
Tony Gwynn died at age 54 after battling salivary gland cancer . He 's not the only MLB player to battle oral cancer . MLB implemented rules in 2011 but has n't banned tobacco use on the field .