Pro sports heading toward robotic future

For most of sports history, there was no recourse when a referee made a bad call. Fans could boo and players could complain, but the game went on. Instant replay changed that a few decades ago, allowing coaches to challenge a call and ask the referees to review it. That made games fairer, but it also made them slower.

Now, many professional sports are on the verge of a new technological breakthrough: automated referee systems, which get the call right every time and significantly reduce delays from reviews.

Leagues insist that these systems, which they are testing in the minors or in preseason games, are not meant to eliminate officials. Umpires and referees are still necessary to make nuanced calls — checked swings in baseball, charging in basketball, pass interference in football. But the leagues believe automated systems could make games both fairer and faster.