The goaltender made 36 saves as the Canadians defeated the United States 2-1 to stay perfect after three games at the world junior hockey championship.
Subban, who plays for the OHL's Belleville Bulls, made a number of game-saving and game-changing stops. Coming into the tournament, there were questions about his concentration after he yielded questionable goals during selection camp and pre-camp, as well as his propensity to give up long rebounds.
The 19-year-old put those questions to rest against the Americans and reinforced both his confidence and his teammates' faith as Canada moves towards the medal round.
"We needed that," Canadian coach Steve Spott said. "You have to have elite goaltending to win this tournament. We've seen it over the last number of years that you need your goaltender to be your best penalty killer and certainly he was tonight."
Subban didn't play badly in wins over Germany and Slovakia, in which he allowed three goals on 28 shots in each. But the Boston Bruins prospect stepped up his game against the U.S. for his best of the tournament so far.
"No one deserves it more than him," Canadian forward Ryan Strome said. "He proved a lot of people wrong. We knew he had it in him."
Strome and Ryan Nugent-Hopkins scored goals for Canada, whose biggest game of the preliminary round now looms Monday against host Russia.
The battle of the unbeaten teams will determine which country tops Pool B and gets the bye to the semifinal. The loser must advance to the semifinal via a quarter-final win.
Canada sits first in the group at 3-0 with nine points, followed by Russia at 2-0-1 with eight. The U.S. and Slovakia, both with a win and three points apiece, meet Monday to determine the group's third playoff team.
Defending champion Sweden tops Pool A with eight points, followed by the Czech Republic with six and Finland and Switzerland tied with five heading into the final day of preliminary-round games.
Defenceman Jacob Trouba scored for the Americans. John Gibson, who plays for Spott's Kitchener Rangers of the OHL, made it a goaltender's duel with 30 saves
After the win, Subban wore the black nylon cape that Canadian coaches award to the game's hero.
He stopped John Gaudreau on a breakaway in the first period and held off an American flurry during a double minor to Canada's Griffin Reinhart early in the second. But it was an opening stop on Trouba that got Subban in a groove.
"I felt really confident coming into the game and after that save, my confidence went right through the roof after that," Subban explained. "It's not so much that it was a tough save.
"I felt really good making the save, I felt comfortable making it, so I think that was the biggest thing for me."
Canada played with 11 forwards because JC Lipon and Boone Jenner were serving suspensions. They will be back in Canada's lineup against Russia, but Spott was forced to furiously juggle his second, third and fourth forward lines Sunday.
"It was really a character win in a lot of ways," Spott said. "The moral of the story tonight is our depth players, our penalty killers, (and) you know, obviously, Malcolm Subban.
"I'm really proud of him. It's a big moment for Malcolm. He stood up tall to the task tonight."
Canada had to kill off a boarding penalty to Nugent-Hopkins with one minute 37 seconds remaining in the game.
"It was pretty nerve-wracking for sure," Canada's captain said. "Something that I can't be doing obviously. I'm obviously happy we got a big penalty kill."
After Trouba's goal pulled the U.S. within a goal at 11:02 of the third, the Americans hurt their own comeback attempt with penalties.
Captain Jake McCabe and forward Ryan Hartman took misconducts for checking to the head later in the third period. Trouba and forward Tyler Biggs took minors as well.
The U.S., which finished seventh in the 2012 tournament, has lost back-to-back games by one goal after also suffering a 2-1 loss to the Russians.
"We had our chances," coach Phil Housley said. "It's one thing if you're not getting the opportunities to score, but we are. We've played two very good hockey teams and had a chance to tie the game in both."
When Ty Rattie and Phil Danault were foiled on a short-handed, 2-on-1 scoring chance, Trouba scored a power-play goal on the following rush back to Canada's end.
Strome made it 2-0 at 18:19 of the first period with his fourth of the tournament. Brett Ritchie worked the puck out from behind the net and Strome snapped it upstairs on Gibson.
Nugent-Hopkins opened the scoring for Canada at 7:13 in the first period, when his team won the faceoff in the U.S. zone. He feathered a low wrist shot past Gibson.
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