Credit: The Associated Press
FILE - In this March 8, 2015, file photo, Seattle Mariners' J.A. Happ throws a pitch between innings as pitch clock counts down in the background during a spring training baseball game against the Cincinnati Reds in Goodyear, Ariz. Major League Baseball and its players are discussing bold changes to spark the sport that include a three-batter minimum before a pitching change except at the start of an inning, a single trade deadline set before the All-Star break and expanding rosters. (AP Photo/Ross D. Franklin, File) 
NEW YORK (AP) — Major League Baseball and its players are discussing bold changes to spark the sport that include a three-batter minimum before a pitching change except at the start of an inning, a single trade deadline set before the All-Star break and expanded rosters.