The Ottawa Fury boasted the best defensive record during the North American Soccer League regular season, its back line winning plaudits for its stinginess and organization.

So how much of a kick in the pants was it that a trio of defensive miscues cost the Fury in the biggest game in franchise history?

Gaston Cellerino scored a hat trick to guide the New York Cosmos to a 3-2 victory over Ottawa in Sunday’s NASL’s Soccer Bowl, the league’s championship final, in Hempstead, N.Y. Tom Heinemann scored both goals for Ottawa, who was reduced to 10 men after Canadian defender Mason Trafford was red carded in the 67th minute.

“I am incredibly proud of this group of men,” Fury coach Marc Dos Santos said after the match. “This is a team of champions. We played like champions tonight, but didn’t get the result.”

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Ottawa conceded only 23 goals in 30 regular season games in 2015, the back four of Ryan Richter, Rafael Alves, Colin Falvey and Trafford proving to be the bedrock of a Fury side that entered the playoffs as the hottest team in the league.

But the defence was caught napping and flat-footed on Cellerino’s opening goal. Richter’s attempted clearance near the centre line bounced off Danny Szetela, and the New York midfielder chased it down, beating Alves to the ball. Some of the Fury players stood still for a moment, thinking the referee would whistle the play dead for Alves’ high foot.

Instead, he played the advantage as Cellerino collected Szetela’s header on the edge of the box, and then fought off three Ottawa defenders before slotting it past goalkeeper Romuald Peiser.

It really was a comedy of defensive errors from a team that is known for its defensive prowess.

Cellerino should have made it 2-0 in the 46th minute when he got in behind Trafford down the left side. Walter Restrepo whipped a perfect ball from the right flank across to Cellerino, who somehow managed to fire his shot from inside the six-yard box over the crossbar with the goal wide open.

Ottawa exerted a little more pressure and began to dictate the pace of the game before Trafford was sent off when he was judged to have stamped New York’s Sebastian Guenzatti with two feet while trying to avoid a tackle. It was clearly an accident and unintentional, but Trafford was reckless and deserved the red card.

Amazingly, Ottawa tied things up just two minutes later when former Toronto FC forward Andrew Wiedeman played a perfect through ball for Heinemann to toe poke home with a lovely finish.

But New York retook the lead in the 73rd minute when Cellerino scored a scrappy goal inside the box. Ottawa substitute Jeremy Gagnon-Lapare squandered a glorious chance to clear the ball from deep inside the box, allowing Restrepo to float a cross to the far post that led to Cellerino’s goal.

Cellerino completed his hat trick in the 85th minute, beating Ottawa’s offside trap and breaking in alone before firing past Peiser.

Heinemann added another goal for Ottawa in injury time, but it was too little, too late.

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Eleven teams from across the United States and Canada compete in the NASL, a second-tier division that’s one level below Major League Soccer. This was Ottawa’s second year in the league.

Sunday’s Soccer Bowl was a meeting between the two best clubs during the regular season—New York and Ottawa finished tied for first place with 15-4-11 records and had an identical goal difference of plus-19. But the Cosmos earned home-field advantage thanks to a superior goals total.

They also split the regular season series, with one win apiece and a draw. New York went 11-3-1 at home in 2015, with Ottawa being the only club to defeat them at home in the last two seasons— a 4-1 win on Sept. 22 the last time these teams faced each other.

The Fury was unbeaten in a league-record 13 games (8-0-5) before Sunday, with just one loss in its previous 26 matches overall (with 15 wins).

Former Toronto FC designated player Julian de Guzman plays for Ottawa, but the veteran midfielder was away on international duty with Canada and was unavailable for Sunday’s championship.

Spanish icons Raul, formerly of Real Madrid, and Marcos Senna, a key member of Spain’s Euro 2008-winning side, play for the Cosmos, and announced they would retire at the end of the season.