You could understand their surprise.

Nearly every season, the Ridgefield High boys hockey program produces a team that is ranked among the top 10 in Connecticut. The Tigers usually have a few of the state’s best players, and they routinely challenge for a championship in the Fairfield County Interscholastic Athletic Conference, one of Connecticut’s most demanding leagues.

Using that pedigree as source material, observers both casual and connected figured Ridgefield surely must have won at least one Division 1 state title since its varsity debut in the 1970s, when Gregg Hutchings was the first star player and the team played in a barn-like home arena liquid-nitrogen cold.

But they didn’t then, and they didn’t through all the subsequent seasons, even when they had a guy named Chris Winnes, who went on to play in the National Hockey League. Truth be told, the Tigers had never even made it to the D1 finals.

Similar assumptions will be accurate going forward.

Monday night made sure of that. Scoring three goals in the first and third periods, Ridgefield defeated Northwest Catholic, 6-2, at Yale University’s always spectacular Ingalls Rink to win the first Division 1 state championship in program history.

“Some people thought we had already won a D1 title,” said head coach Shaun Gallagher. “We hadn’t. Now we have.”

It certainly wasn’t a fluke. Ridgefield spent nearly all of 2016-17 ranked first in every state poll and won 18 of 20 regular-season games. The Tigers then stormed through the FCIAC playoffs, beating New Canaan, 5-2, in the finals to win the conference championship for the sixth time in program history.

Seeded second (based on regular-season record and quality points) in Division 1, Ridgefield scored three unanswered goals in the third period to oust two-time reigning champion Darien, 4-1, in the opening round before edging perennial power Fairfield Prep, 4-3, in overtime in the quarterfinals.

That victory — Ridgefield’s first over Prep in the state tournament — was the Tigers’ signature triumph of the season. Down 3-1 entering the third period, Ridgefield scored twice to tie the game and then got the game-winner from Nick Cullinan early in overtime.

Three third-period goals broke a 1-1 tie and lifted the Tigers past West Haven, 5-1, in the semifinals, and another superb effort followed in the final 15 minutes of Monday’s state final.

After top-seed Northwest Catholic scored the only two goals of the second period to close within 3-2, Ridgefield regained control when Will Forrest spotted a loose puck scored less than a minute into the final period. Two more goals followed, as the Tigers left no doubt about who was the state’s top team.

“The third period has been our best all season, going back to a preseason scrimmage against St. John’s Prep,” said Gallagher. “We’ve had a lot of really good teams here (Ridgefield won a Division 2 state title back in 2002), but one thing that separates this team is its mental composure and toughness. If we got scored on we would attack and score right back.

“That’s why the players were not worried between the second and third periods against Northwest Catholic,” continued Gallagher. “They knew the third period has been good for us this year.”

Monday night was no exception. The combination of skilled depth — Ridgefield skated three productive lines and six defensemen — and the saves of senior goalie Sean Keegans flummoxed opponents late in games all season. Despite having three of the state’s best forwards, Northwest Catholic was no exception.

As the Ridgefield fans counted down the final seconds, the obvious became official: The Tigers were Division 1 champs. No surprise.