MLB to Test Three Experimental Rules in Atlantic League, Including Designated Pinch Runner.
Major League Baseball (MLB) will test three new rules in the independent Atlantic League, including the use of a designated pinch runner, the "double hook" DH rule, and further limitations on mound visits. The Atlantic League season starts on April 28, and the experiments will be tested during the season. MLB has previously used the Atlantic League as a rules laboratory and typically tests successful rules in the affiliated minor leagues before considering them for use at the big-league level.