The Flyers have apparently discovered a vaccine that prevents losing streaks.

Or maybe they just pay more attention to details and get more focused after an embarrassing defeat.

Nine times since early January, they have been beaten. Nine times they have rebounded and won the next game, including their most important bounce-back victory to date, a 1-0 verdict Sunday night against eighth-seeded Montreal in Toronto.

The win, which followed Friday’s 5-0 debacle, gave the top-seeded Flyers a 2-1 lead in the best-of-seven Eastern Conference quarterfinal. In NHL history, teams that take a 2-1 series lead have gone on to win 67% of the time.

Game 4 is Tuesday at 3 p.m.

Jake Voracek’s first-period goal and Carter Hart’s strong goaltending carried the Flyers, who haven’t lost two or more straight since Jan. 7. They are also now 5-0 in games that follow a loss of four goals or more this season.

“We all responded,” Hart said. “We knew Game 2 wasn’t our best and nowhere near our capability of playing.”

Hart, 22, who made 23 saves and notched his first playoff shutout, was both excellent and fortunate as the Canadiens hit iron on five shots. Hart became the youngest goalie in franchise history to notch a shutout.

“We were able to grease it out, and Carter made some big saves,” coach Alain Vigneault said. “... It was hard to make offensive plays. Both teams were not giving a lot of room on the ice. You’ve got to grind these out.”

Hart robbed Jesperi Kotkaniemi, who came in alone after an Ivan Provorov miscue, to preserve the win with 50.4 seconds left.

In the previous game, Hart, though not at fault, was pulled late in the second period as the Flyers fell behind, 4-0.

“It’s a good thing he’s a little too oblivious to some things [like] being a goalie in Philadelphia,” cracked Voracek. “He’s very strong mentally. He’s pretty impressive the way he bounces back. That’s what good goalies do.”

“I just have to do my job. That’s what it comes down to at the end of the day,” Hart said. “We have a great crew in front of us that makes my job a lot easier.”

The Flyers were far from perfect. They were on their heels in the second half of the game, and their power play was powerless as it went 0-for-6 and is now (gulp) 1-for-25 (4%) in the postseason.

With the Flyers clinging to a 1-0 lead, Kotkaniemi, who had two goals in Game 2, hit the post in the opening minute of the third period.

The Flyers allowed a shorthanded two-on-one with about 7½ minutes left, but Hart turned aside Artturi Lehkonen just after the Montreal penalty expired.

Montreal Canadiens center Nick Suzuki (14) is stopped by Carter Hart (79) during the second period of the Flyers' 1-0 win Sunday. Hart became the youngest goalie in Flyers history to notch a playoff shutout.
Frank Gunn / AP
Montreal Canadiens center Nick Suzuki (14) is stopped by Carter Hart (79) during the second period of the Flyers' 1-0 win Sunday. Hart became the youngest goalie in Flyers history to notch a playoff shutout.

Earlier in the day, the Flyers got inspiration from having left winger Oskar Lindblom take part in the morning skate. He has spent most of the season battling a rare bone cancer.

“It’s always a big boost when he’s around,” said defenseman Robert Hagg, a fellow Swede who is Lindblom’s closest friend on the team.

The Flyers blocked 24 shots — 14 more than the Canadiens. Matt Niskanen led the way with six blocks.

“That’s what you have to do to win games,” Hagg said. “Every single guy in the locker room did a great job.”

“Guys were laying it on the line,” Vigneault said. “That’s what you need in playoff hockey. Those shot blocks are sometimes as important as great offensive looks.”

The Flyers’ awful first period in Game 2 set the tone for the Canadiens’ blowout win. This first period was different. Much different. The Flyers played with more physicality than Friday, built a 1-0 lead, and spent a good portion of the opening 20 minutes in Montreal’s end.

Hart was tested 31 seconds into the game, and he denied Brett Kulak at the doorstep after the Montreal defenseman joined the rush.

About five minutes later, Voracek gave the Flyers the 1-0 lead, the fifth time in six postseason games they had scored first. Voracek was moved from the third line back to the top unit, where he played during the Flyers’ nine-game winning streak late in the regular season.

Claude Giroux’s shot from near the top of the left circle was redirected by Voracek past Carey Price, who had given up a fat rebound about a half minute earlier and was fortunate Kevin Hayes fired wide after he retrieved the puck.

JThe Flyers' ake Voracek (93) celebrates his goal against the Montreal Canadiens with Sean Couturier (14) during the first period of Game 3 on Sunday in Toronto.
Frank Gunn / AP
JThe Flyers' ake Voracek (93) celebrates his goal against the Montreal Canadiens with Sean Couturier (14) during the first period of Game 3 on Sunday in Toronto.

Down the other end, Hart was also fortunate. Twice. First, the ever-present Kotkaniemi hit the left post and, on the same shift, Kulak had a shot carom off the right post with 11:44 to go in the first.

The Flyers got a four-minute power play a short time later after Kotkaniemi got a double minor for high-sticking Nate Thompson. Travis Konecny, who suffered an apparent ankle injury in Game 2 and had been questionable for Sunday’s game, hit the post on the Flyers’ best power-play chance, and Price denied Voracek in front on another great opportunity.

Three first-period penalties kept the Canadiens on defense for much of the opening period. The same could be said for the Flyers in the second period, when they gave Montreal three power plays.

Hart maintained the Flyers’ 1-0 lead by making a key save on Brendan Gallagher early in the second, and stopping Jonathan Drouin on a mini-breakaway with 3:25 left in the period. Both scoring chances were set up by turnovers committed by Scott Laughton, who owes his young goalie a dinner or two.

The Flyers had another scary moment with 6:09 remaining in the second. But Nick Suzuki, on a two-on-one shorthanded chance, whipped a shot off the outside of the right post.

Hart said the Flyers had a “nice little pool workout” to get their minds off the 5-0 loss in Game 2.

“It ended up being competition for who could hold their breath under the water the longest and swim the farthest,” he said with a laugh, “so that was pretty fun. Just had some fun with the boys to get away from the game a little bit.”

Breakaways

The Flyers outhit the Canadiens, 36-23. Konecny, Michael Raffl, and Sean Couturier each had five hits. ... Pete Peeters had been the youngest Flyers goalie to register a playoff shutout, doing it in 1980. ... It was just the Flyers’ fifth 1-0 win in their playoff history. ... Vigneault made two lineup changes, inserting fourth-line left winger Raffl, who hadn’t played since Aug. 2 because of a leg injury, and Hagg into the lineup. Rookie winger Joel Farabee and defenseman Shayne Gostisbehere were healthy scratches. ... Hagg (three blocked shots, three hits) had an assist, the first playoff point of his career. ... The Flyers had a total of three shots on their six power-play chances.