The first night started with Canadiens star defenseman P.K. Subban being ejected for slashing the wrist of Senators forward Mark Stone, continued with a five-period thriller between the Blackhawks and Predators, and, fittingly, concluded with a late game-winner in Vancouver.

MORE: Must-see photos | Ranking the playoff teams | Why each team will lose | Playoff scoreboard

Canadiens 4, Senators 3 (Montreal leads series 1-0)

The second period provided most of the excitement in this one, starting with Subban’s slash that ignited what promises to be a chippy series. He received a five-minute major and a game misconduct, which was followed by a flurry of six goals in a span of 9 minutes, 23 seconds. Canadiens trade deadline acquisition Brian Flynn had the last say, scoring the eventual game-winner with 2:43 remaining in the period.

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Subban’s hack created plenty of tension, which poured over postgame.

“I think it’s an easy solution: You either suspend him or one of their best players gets slashed and just give us five (minutes),” Senators coach Dave Cameron told reporters.

MORE: Game highlights

Some claimed Subban’s ejection was excessive, that the slash warranted a double minor at most.

‘‘I agree it was a slashing penalty but I don’t agree that it deserved five minutes,’’ Canadiens coach Michel Therrien told reporters.

Stone, who left the game after the slash but later returned, wasn’t buying it. He accused Subban of intent to injure.

“He tried targeting me a couple times in the first period off faceoffs,” he said. “I think he knew what he was doing.”

Flynn also had two assists. Torrey Mitchell, Tomas Plekanec and Lars Eller also scored for the Habs. Kyle Turris, Milan Michalek and Mika Zibanejad had the Sens’ goals.

Islanders 4, Capitals 1 (New York leads series 1-0)

Led by a trio of young forwards, the Islanders turned some doubters into believers with the only blowout of the night.

Brock Nelson, Josh Bailey and Ryan Strome — all under 25 — scored for New York, which wasn’t exactly a popular pick to advance to the second round after drawing red-hot Washington. Nelson opened the scoring 6:06 into the first period, followed by Strome (3:50) and Bailey (10:36) in the second period. Nelson scored an empty-netter at 18:41 of the third period.

MORE: Video highlights

Islanders goalie Jaroslav Halak earned the win, stopping 24 of 25 shots.

‘‘We’re going to have to be a lot sharper. That goes right through the whole lineup,’’ Capitals coach Barry Trotz told reporters. ‘‘I thought from our top guys to our role players, there wasn’t too many sharp guys.’’

Blackhawks 4, Predators 3, 2 OTs (Chicago leads series 1-0)

After the way it started, who could have guessed this game would turn into a goalie duel? 

Nashville scored three goals on 12 shots in the first period. Chicago pulled starting goalie Corey Crawford in favor of Scott Darling, who spend most of the first half of the season with AHL Rockford. Darling dazzled in his playoff debut and allowed the ‘Hawks to mount a comeback in the second and third periods.

The game carried into a second overtime before Duncan Keith scored 7:49 into Period 5.

MORE: Video of Keith’s goal | Full game highlights

Niklas Hjalmarsson, Patrick Sharp and Jonathan Toews also had goals for Chicago. Predators goalie Pekka Rinne stopped 38 of 42 shots.

“Guys played great in front of me,” Darling told reporters. “They didn’t help Crow (Crawford) very much but they turned it around and made my life easy.”

Blackhawks coach Joel Quenneville declined to name a starter for Game 2.

Flames 2, Canucks 1 (Calgary leads series 1-0)

Held scoreless through two periods, the Flames got on the board 7:30 into the third period on a goal by David Jones. It appeared the game was headed for overtime, but a slap shot by Kris Russell with 30 seconds remaining in regulation gave Calgary its first playoff win since 2009.

MORE: Video of Russell’s goal | Game highlights

Flames goalie Jonas Hiller was the real star. He turned aside 29 of 30 Canucks shots. 

Three stars

  1. Brian Flynn, F, Canadiens: His three-point game was the best of his career. He hadn’t scored a point in nine games since being acquired by the Habs at the deadline.

  2. Jonathan Toews, F, Blackhawks: He, too, had a goal and two assists, including one on Keith’s game-winner. He also had four shots.

  3. Scott Darling, G, Blackhawks: He stopped all 43 shots he faced in relief of Crawford.

Injury report

Mark Stone, F, Senators: Stone left the game after catching Subban’s slash in the wrist but returned shortly after. It was later revealed he suffered a microfracture in his wrist.

Patrick Kane, F, Blackhawks: He picked up two assists in his first game since breaking his clavicle in February.

Highlight

Things didn’t start great for the Canadiens.

The first goal of the series was scored by Andre Markov. The only problem was that he scored it on Carey Price, who, as you know, is a teammate of Markov’s. The play was more of an unfortunate blunder as Markov appeared to just lose control of the puck in front of Price. Still, not the beginning they envisioned.

Thursday’s games

(All times Eastern)

Penguins at Rangers, 7 p.m.

Red Wings at Lightning, 7:30 p.m.

Wild at Blues, 9:30 p.m.

Jets at Ducks, 10:30 p.m.