“We just played fast,” said Matthews, who led the NHL with 60 regular-season goals. “We played through the contact.”
Mitch Marner had a goal and two assists. Jake Muzzin scored and David Kampf added a goal on a short-handed breakaway for Toronto, which killed off five Lightning power plays, including an early five-minute major.
Marner, meanwhile, snapped a playoff slump in which he had gone 18 contests without scoring.
“Can’t do anything about the past,” Marner said. “I’m here to focus on the now. I’m here to focus on what I can do to help team our team win.
“Just like everyone else in that locker room.”
Andrei Vasilevskiy stopped 28 shots for the Lightning.
“I’m not so sure the Maple Leafs had to play particularly well to beat us tonight,” Lightning head coach Jon Cooper said. “You’ve got to win four and you don’t want to give teams any freebies and we probably gave them a little bit of a freebie.
Toronto called a timeout ahead of a 5-on-3 power play in second and took just 11 seconds to score with five forwards on the ice. Marner fed Matthews, whose shot beat Vasilevskiy to the short side.
Tampa got its fourth man advantage later in the period, but Kampf beat Victor Hedman to a loose puck as Toronto once again showed its superior speed before beating Vasilevskiy to make it 3-0 at 9:27.
Campbell had to be sharp at the other end on another Lightning power play. He made a nice blocker stop on Brayden Point off a Nikita Kucherov feed. Steven Stamkos then heeled a one-timer.
“It’s a funky game,” Keefe said. “There’s so much special teams. I don’t even know how we’re gonna process this one.
“There’s so many things happening that are not necessarily normal, and we shouldn’t expect to be the norm going forward.”
The Leafs put the game out of reach at 16:39, when Marner snapped his long playoff goal drought. The winger took a slick pass from Morgan Rielly off the rush and beat Vasilevskiy for his first playoff goal since April 11, 2019, a stretch of 18 games.
Toronto kept pressing into the third period. Matthews made it 5-0 when Vasilevskiy misplayed the puck behind his net and he scored his second at 8:16.
“The boys just played so hard,” Campbell said. “They’re an amazing team over there. They’re not going to be thrilled about the Game 1.”
The game took another violent turn midway through the period with multiple fights on one shift. Rielly cut Lightning defenseman Jan Rutta in one skirmish, and the Lightning’s Pat Maroon and Corey Perry, and Toronto’s Wayne Simmonds and Ilya Lyubushkin were also sent to the locker rooms with misconducts.
Keefe said he didn’t like Clifford’s penalty early, but was happy with his team’s response when the Lightning tried to mix things up with the outcome decided.
“We were physical when the game called for it,” Keefe said. “We handled their physicality well both in making plays and keeping the puck moving and not getting rattled by it.
“And then just standing our ground when the nonsense starts.”
The Leafs have lost seven straight post-season series and haven’t advanced to the second round since 2004. They absorbed a crushing seven-game loss last season when the Montreal Canadiens stormed back from a 3-1 deficit.
The Lightning have won eight straight series since a stunning sweep at the hands of the Columbus Blue Jackets in 2019, following a 128-point campaign and the franchise’s first Presidents’ Trophy.
NOTES: The Maple Leafs hit the ice for Game 1 on the 55-year anniversary of the franchise’s last Stanley Cup. … Toronto had winger Ondrej Kase in the lineup after he missed the last 20 regular-season games with a concussion. Top-line winger Michael Bunting sat out a fourth straight contest with an undisclosed injury. … Forward Jason Spezza was a healthy scratch for Toronto. … Zach Bogosian sat out for the Lightning. … The third and fourth games in the series are set for Friday and Sunday in Tampa.
More AP NHL: https://apnews.com/hub/NHL and https://twitter.com/AP_Sports