If the Canadiens avoid a sweep, they will play Game 5 against the Lightning at home. If the Rangers avoid elimination, they will get to Game 6.
Dates, times and TV information for those games was disclosed Thursday by the NHL. Both series are in the Eastern Conference in the Stanley Cup playoffs.
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First up: a potential series finale between the Habs and Bolts in Tampa. Game time: 7 p.m. ET. on NBC Sports Network.
Thanks to Tyler Johnson's backbreaking goal with one second left in regulation, the Lightning won Game 3. They are now 8-0 against the Canadiens this season.
Game 5 in the series, if necessary, would be played at Montreal's Bell Centre on Saturday. TV coverage: NBC Sports Network in the States, CBC and French-language TVA Sports in Canada.
Also Thursday, the Blackhawks go for a sweep of the Wild. Win, and the 'Hawks go to the Western Conference finals. Game time: 9:30 p.m. ET on NBC Sports Network.
The Rangers' bid to return to the Stanley Cup finals is in doubt, and they are down 3-1 to the Caps as they prepare for Friday's 7 p.m. ET game at Madison Square Garden. TV coverage: NBC Sports Network, CBC and TVA Sports.
If the Rangers win, Game 6 will be played Sunday at Verizon Center in D.C. Start time: 7 p.m. ET. TV coverage: NBC Sports Network, CBC and TVA Sports.
The other remaining playoff series finds the Ducks up 2-1 on the Flames. Game 4 in that series is set for 9:30 p.m. ET Friday. TV coverage: NBC Sports Network, CBC and TVA Sports.