To the eye, Torey Krug scored at 3:17 of Saturday’s second period to give the Bruins a 2-0 lead over the Capitals. It was Krug’s first goal since Dec. 5.

But to an undisclosed camera positioned somewhere in TD Garden, Krug was not eligible to bust his 37-game goal-scoring drought. Upon video review, linesmen David Brisebois and Derek Nansen determined Loui Eriksson had gone offside before Krug slipped the puck past Philipp Grubauer.

“If it’s offside, then it’s not a goal,’’ said Krug. “It’s frustrating. I haven’t scored in a while. But it’s a good test for your character and trying to respond. I still have the faith. Right time, right place, it’ll happen.’’

Whatever that clip was, it was not shown on NESN, on the TD Garden scoreboard, or perhaps not even on Claude Julien’s laptop.

“We’re not all 100 percent on board with some of that stuff,’’ Julien said of he and his fellow coaches on the challenge following the Bruins’ 2-1 overtime loss. “But you’ve got to live with it. You live with it, because we always compare it to other calls we’ve had, whether it’s with other games and stuff like that. I guess we don’t always see consistency. But who are we?’’

Brisebois and Nansen must have seen a review that clearly showed Eriksson entering the offensive zone before David Pastrnak carried the puck over the blue line. Otherwise, they would not have overturned the original call. This is forbidden by the league.

According to Rule 78.7, which governs the coach’s challenge, if a review is not conclusive and/or there is any doubt whatsoever as to whether the on-ice call was correct, the linesmen are instructed to confirm the original call.

The trouble is that with offside, rarely is a review conclusive.

The NHL’s linesmen are as good at what they do as any officials in any sport. It is just about impossible to judge whether a big, fast-moving man enters the offensive zone a hair before the puck. Yet the linesmen almost always get the calls right. They never blow them to the extent where a replay shows, without question, that a play was offside.

And that’s the issue with the cuckoo coach’s challenge. Given the nature of the play, a review will never be conclusive. There will always be doubt, unless the league wants to advance this technology nonsense to a greater degree.

How about lasers at each blue line? How about we install sensors in pucks and on players? How about a player gets an electric shock if he enters the offensive zone ahead of the puck? How about players’ skaters lock up, like the wheels on a shopping cart when it goes outside the parking lot, when an offside takes place?

There were good intentions behind the coach’s challenge. Execution, however, has proven it is a worthless exercise.

If Eriksson was a shade offside, it had no bearing on the outcome of the play. Pastrnak carried the puck into the zone and snapped the puck on goal. Grubauer stopped the shot but couldn’t control the rebound. Krug got to the puck before a backchecking Jason Chimera could slow him. The defenseman winged the rebound past Grubauer to give the Bruins a 2-0 lead.

Or so he thought. The goal was disallowed. Less than 10 minutes later, Karl Alzner tied the game, 1-1. What would have been a pivotal strike by the Bruins went up in smoke.

“It’s disappointing,’’ Brad Marchand said of the disallowed goal. “You’re up 2-0. It’s a big difference. We get that one taken back and they score shortly after. That’s enough to change the game.’’

Everything is lousy about the procedure. The reviews take too long. A lively rink loses all its juice while the officials squint at their tablet. All the rhythm of the fastest game in the world goes missing when the coaches start using their challenges.

“In a game, you have to stick with it no matter what happens,’’ Patrice Bergeron said. “It’s one of those things where it is part of the game right now, the coach’s challenge, and some of the calls you can argue with. But, at the same time at the end of the day, they have the last call and they have to make a quick decision.’’

Nobody can blame the coaches for using their misfit challenge. It’s gotten to the point where coaches such as Barry Trotz will question anything that is close, whether it’s an offside or goaltender interference call. It’s become a coin flip. There is no consistency with anything surrounding the play. It has become a farce, starting with the tablets that are too small to see the screen, let alone the puck. A coach is willing to sacrifice his timeout when the odds are 50-50 that a goal will come back.

Julien has said that he likes the challenges. The bottom line, Julien believes, is to get the calls right. But there’s no agreement on whether the challenges are resulting in correct calls.

The inconsistency has turned the process into a shrug. That’s no way for a fast, instinctive, and competitive sport to be judged.

Fluto Shinzawa can be reached at fshinzawa@globe.com. Follow him on Twitter @GlobeFluto.