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.

State of the tools

Technology is built into the rules of professional sports. The US’ National Football League (NFL) requires instant-replay reviews of all scoring plays and turnovers to ensure that the calls are right.

That was on display on the final play of the season-opening game in Kansas City. Baltimore Ravens tight end Isaiah Likely caught a potential game-tying pass in the back of the end zone. But after a 90-second video review, officials determined that Likely’s toe was out of bounds, negating the pass and handing Kansas City the win.

It was an example of what technology does best in sports: help referees make a decision about an easily defined play. But it also highlighted one pitfall of the current system: For fans, that 90-second wait can feel a lot longer.

Automating those decisions would allow games to move more quickly. And for one sport, that has already happened at the highest level. Sony’s Hawk-Eye Live system, which for years allowed tennis players to challenge calls and see exactly where a shot had landed, has gotten so good that it now handles all the line calls at the US Open and the Australian Open.

On the horizon

America’s big professional sports leagues have not moved to automated refereeing yet, but most of them are testing their own systems.

Baseball appears to be nearing a major change. It has used a system that automatically determines whether a pitch is a ball or a strike in its minor leagues, across more than 8,000 games. The system could make its first appearance in the majors next year, when the league may test it during spring training.

The NFL is also testing computerised officiating. This past preseason, the league introduced cameras that help spot the ball after plays. The technology could mean the end of the chain gangs who run onto the field with two poles connected by a 10-yard chain to measure first downs.

And the NBA is testing technology to automatically detect goaltending calls, which involves determining whether the ball was moving upward or downward when it was blocked.

The human element

When baseball began testing its automatic umpire system in the minor leagues, it introduced two variations. One determines balls and strikes on every pitch and notifies the umpire, who signals the result. The second variation, which uses the same technology, is called upon only when a pitcher, catcher or batter challenges an umpire’s call.

Umpires have been right on about half of those challenged calls. But players still said they preferred the challenge system to the automated one. Some said that challenges add a strategic element.

“Originally, we thought everybody was going to be wholeheartedly in favor” of the fully automatic calls, said MLB Commissioner Rob Manfred. But, he said, “players feel there could be other effects on the game that would be negative if you used it full-blown.”

Rich McKay, CEO of the Atlanta Falcons, leads the NFL’s committee on game rules and had similar feelings about the potential for automated calls in football.

“When you take the officiating out of the game and try to put it in a different place, I’m just nervous about what that leads to,” he said. “You’d have to rewrite all the rules.”

 - NY Times