The term comes from the dead man’s hand, the fabled poker hand containing both black aces and two eights. As the legend goes, the Old West gunfighter, lawman and gambler Wild Bill Hickok was holding the hand when he was murdered in 1876. Eddie Shore, an N.H.L. star in the 1920s and ’30s and later an A.H.L. owner and coach, is believed to have brought the term to hockey, adopting it to refer to players working their way back into the lineup.

The distinction has taken on new meaning in the modern N.H.L. as a promotion that tends to involve plenty of watching and waiting.

“Typically, the playoffs in the N.H.L. are so long that usually there’s a couple of guys who get banged up. So there’s always a good chance,” Carpenter said. “That’s pretty much what they told us. Just to be ready. You’ve got to look at it as a really good thing and a great opportunity.”

As remote as the opportunity may seem, there is a precedent for Black Aces getting the call in the Stanley Cup finals. Earlier this season, Carpenter and Goldobin did not need to look too far to find a player who could attest as much.

Ben Smith spent much of this season playing with the Barracudas before being traded to the Toronto Maple Leafs on Feb. 27. But after beginning the 2013 playoffs as a Black Ace with the Chicago Blackhawks, Smith was thrust into duty in Boston against the Bruins in Game 3 of the finals because of an injury to Marian Hossa.