That’s right, the onsite head referee during a NHL game, for example, calls in to the league’s NHL Situation Room located inside its headquarters in Toronto, Canada and an official stationed there helps make the call. During NBA games, that call goes to the NBA Replay Center, in Secaucus, New Jersey and with MLB games, the decision is made at the MLB Advanced Media’s Replay Operations Center (ROC), located in New York city.

Again, the goal is to cut down on the wait time. League officials have said the majority of reviews take 60 to 90 seconds, although close calls with inconclusive camera angles could easily take longer. MLB’s average wait time for a decision during the 2014 season, for example, hovered around after 2 minutes and 14 seconds.

“[We’ve created] a central location where we’ll have people there who will be watching every game,” NBA president of basketball operations Rod Thorn told ESPN.com. “When the referees go over to the side, in many instances the [central replay center] will already know what happened and they’ll be able to tell the referee, which will hopefully take less time.”

It’s the technology implemented that’s making it happen. During this fall’s 2014 World Series between the San Francisco Giants and the Kansas City Royals—the first time an instant replay was used to make a call during a World Series game—the onsite umpires and MLB used a combination of intercom systems from Clear-Com to support instant replay communications between the 30 Major League ballparks and Replay Operation Centers (ROC) located in New York and San Francisco.

Each ballpark is equipped with a Clear-Com HelixNet Digital Networked Intercom combined with HKB-2X user stations and HBP-2X beltpacks to support communications for the field umpires, ballpark replay technicians, the broadcast truck supporting the game, and the scoreboard official in the ball park. The HelixNet HMS-4X base stations are interfaced to Clear-Com VoICE2 IP interfaces which connect to each of the ROCs.

Within each ROC’s equipment room is a compliment of VoICE2 units that work in tandem with an Eclipse HX Digital Matrix Intercom system. Umpires and replay technicians in the ROCs have V-Series user panels that allow them to communicate with any or all of the games in progress.

Every MLB telecast feeds 12 to 15 camera angles to the ROC in New York, split between the home and away teams' TV truck feeds. Those videos also go to each team to help them decide when to challenge calls.

Similar two-way communications systems are now in place for the NBA and NHL as well.

The NBA’s state-of-the-art NBA Replay Center gives officials numerous enhanced views of the action, which encourages a faster decision. The center features 94 HD monitors (14 for replay operators around the outside and four for replay managers and two for content management and social media on the interior) and 20 Evertz DreamCatcher Replay system workstations.

A single replay operator is designated for each game, proactively reviewing and tagging video for potential reviews (and later repurposing of highlights) Multiple camera angles can be location pieced together and instantaneously streamed to the referee crew chief on the court, who then make the final call.

In all cases the technology involved (replay systems, a direct intercom line and multiple views of the same play) is clearly making a difference. Now, during NBA games, league officials in Secaucus can often make the correct call made by the time the referees in the arena make it to the scorer’s table.

Editor’s Note: While it too might move to a centralised system or all of its 33 teams sometime soon, the NFL, the first professional sports league in the U.S. to use instant replay, still uses an in stadium HD system in all of its venues that features an Imagine Communications (formerly Harris Broadcast) NEXIO HD server as the primary replay server—with another one at each stadium for redundancy. To manage the numerous camera angles, they also use Football Officiating Replay Challenge Expeditor (FORCE) software, routing and distribution gear. The referee sticks his head inside a replay booth on the field, which is networked with an official’s booth on the upper ring of a stadium. The ref can ask for any number of camera angles. The NEXIO HD server systems replaced an aging analog instant replay system in 2007, which have been in use since 1999. Those original replay systems were based on the Leitch VR-300 server, now discontinued.