ALL WORK AND REPLAY

Some of the busiest (and most influential) coaches during the playoffs won't be found in the spotlight—they'll be in the dark

"PAY ATTENTION to that man behind the curtain," the Wizard would have warned Dorothy if Dorothy were an NHL fan. Stashed away in auxiliary locker rooms or cramped offices in the bowels of arenas, surrounded by more screens than an FBI surveillance team, video coaches are hockey's seers. Once just a troop of clip-cutters, these men are now critical to any hockey operation. Thanks to the coaches' challenge, introduced in the 2015--16 season, they now possess enough power to determine the outcome of the Stanley Cup playoffs.

Watch any broadcast. Notice how assistants talk into their cuff links, as if they're Secret Service men? Often they're radioing video coaches, asking if they should challenge a goal for offsides or goalie interference—the only two reviewable scenarios under NHL rules (left).

By installing HD monitors on every bench this season, the NHL gave head coaches the opportunity to check for themselves. But the eyes in the back office, plugged into the same Hawk-Eye system that line judges use in tennis, always see more. "When teams come across the blue line, a lot of times we know it's offside," Capitals coach Barry Trotz says. "If they score, we're challenging it. There's not a lot of hesitation on our side."

The choice isn't always easy. Coaches can only call one timeout per game, which they often use to spell tired skaters or to draw up plays at key moments. Successful challenges carry no penalty, but failure means losing the timeout and the opportunity to contest a call later.

"You're stuck in between sometimes," Ottawa head coach Guy Boucher says. "It's not as easy as I thought it would be."

While challenges don't happen often—teams requested reviews an average of 8.6 times this season, slightly more than once every nine games—the pressure-packed postseason means the Cup could hinge on one shrewd call from the Wizards of Pause.