from Tal Pinchevsky of the New York Times,

In previous years, teams reserved the right to use their own spotters. The in-arena concussion spotters employed by the N.H.L. as off-ice officials were introduced last season. But this year the league installed the central spotters to monitor each game.

Stationed in the same New York war room as the N.H.L.’s Department of Player Safety, a group of one to four spotters — depending on the number of games that day — is responsible for seeking any players exhibiting concussion symptoms.

Working in conjunction with in-arena spotters, the New York-based central spotters, who are certified athletic trainers with training in the visible signs of concussions, communicate with team medical staff if a player requires an evaluation as outlined by the protocol.

“Our goal every year is to evaluate the system we have in place and, to the extent it can be improved, to make the changes necessary to improve it,” N.H.L. Deputy Commissioner Bill Daly said in an email. “The changes we have made to our program and protocol from year to year, and there have been changes made every year, are a reflection of that process and philosophy.”

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