RulesMLB Umpire Manual
Rule 6.01, Definitions of Terms (Interference(a)): While contact may occur between a fielder and runner during a tag attempt, a runner is not allowed to use his hands or arms to commit an obviously malicious or unsportsmanlike act—such as grabbing, tackling, intentionally slapping at the baseball, punching, kicking, flagrantly using his arms or forearms, etc.—to…