The Islanders' Nick Leddy, right, checks the Flames' Garnet Hathaway,...

The Islanders' Nick Leddy, right, checks the Flames' Garnet Hathaway, centre, into goalie Thomas Greiss during the first period on Wednesday, Feb. 20, 2019, in Calgary, Alberta. Credit: AP/Jeff McIntosh

CALGARY, Alberta —  Barry Trotz graded his Islanders with a “Big F.”

“Failure,” the coach said. “We had too many passengers. We weren’t emotionally and physically engaged, at least in the first half of the game. We didn’t deserve to win.”

Yet despite the Pacific Division-leading Flames being decidedly better in all phases on Wednesday night at Scotiabank Saddledome, the Metropolitan Division-leading Islanders somehow managed to erase a two-goal deficit and put themselves in position for an improbable rally. But the Flames scored two third-period goals within 29 seconds to complete a chippy, 4-2 win as the Islanders opened a three-game Western Canada swing that continues on Thursday night at Edmonton.

“They played a good game,” said Thomas Greiss, who made 28 saves and battled more traffic in his crease than the Islanders goalies have been used to seeing this season. “They were faster than us and played a harder game and outbattled us in those areas.”

The Islanders (35-18-6), out-chanced 68-47, had won a franchise record five straight games after falling behind 2-0. But they were coming off a three-day layoff — their longest break the rest of the season — after Saturday night’s 5-2 win over the Oilers at NYCB Live’s Nassau Coliseum.

“It’s always tough, especially this time of the year, when you get a couple of days off, it gets you out of your rhythm,” Greiss said. “But we can’t make any excuses. We know they’re a good team. We’ve got to be ready for it.”

Mike Smith stopped 17 shots for the Flames (37-16-7), who are 19-5-5 at home and second in the NHL in goals scored.

The teams meet again on Tuesday night at the Coliseum.

“We were really rusty to start,” said captain Anders Lee, who tied the score at 2 from the slot at 1:18 of the third period as he reached the 20-goal mark for the third straight season. “We weren’t good enough. I struggled to figure it out and find the puck and that can get really frustrating when you know how big the game is.”

“We were poor on our exits,” Trotz added. “We were poor on our execution. We were poor in our battles. We were poor in our races. We were poor.”

Yet despite being outshot 24-7 in the first two periods, Casey Cizikas brought the Islanders within 2-1 at 10:09 of the second period.

“We didn’t come out hard enough, that’s the bottom line,” said Cizikas, who extended his career high with his 16th goal. “I think we showed them a little too much respect. We didn’t make plays we needed to along the walls and down low in their end. We gave too many pucks away.”

The Flames quickly regained control of the game after the Islanders tied it.

Austin Czarnik was credited with the go-ahead goal to make it 3-2 at 6:10 as the puck deflected in off the Islanders’ Leo Komarov.

Defenseman Nick Leddy was promptly whistled for interference and Johnny Gaudreau connected from the left circle on a power-play goal at 6:39.

The teams combined for 14 penalty minutes in the third period, with Cal Clutterbuck and the Flames’ Mikael Backlund and Garnet Hathaway being called for unsportsmanlike conduct minors.

The Flames took a 1-0 lead at 5:00 of the first period as Backlund got to the crease after taking Michael Frolik’s feed on a two-on-one rush and deked out Greiss.

Former Islanders defenseman Travis Hamonic scored his first goal in three games against his former team with a blast from the right point to make it 2-0 at 15:59 of the first period.

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