NEW YORK – Former Chicago Cubs and Boston Red Sox executive Theo Epstein has been hired by Major League Baseball as a consultant for on-field matters and will evaluate possible rule changes.Epstein will work with baseball Commissioner Rob Manfred, the owners’ competition committee and analytics experts, MLB said Thursday,“As the game evolves, we all have an interest in ensuring the changes we see on the field make the game as entertaining and action-packed as possible for the fans, while preserving all that makes baseball so special,” Epstein said in a statement.MLB is considering possible rules changes such as expanding the designated hitter to the National League.