Ottawa Senators at Toronto Maple Leafs

Marner leads Maple Leafs in 6-2 win over Senators in Game 1

William Nylander and John Tavares each had a goal and an assist, and Oliver Ekman-Larsson, Morgan Rielly and Matthew Knies also scored for Toronto. Auston Matthews added two assists and Anthony Stolarz stopped 31 shots.

“It was intense,” Tavares said. “It’s called the Battle of Ontario for a reason. Hard-fought game. But we know we still can be a lot better.”

Drake Batherson and Ridly Greig scored for Ottawa, and Linus Ullmark finished with 18 saves.

“Have to refocus,” Ullmark said. “It’s just one game. That’s the beauty of it.”

The best-of-seven matchup continues Tuesday with Game 2 at Scotiabank Arena before shifting to Ottawa for two games.

The series opener marked the first playoff Battle of Ontario showdown in exactly 21 years when Toronto bested Ottawa 4-1 in Game 7 on April 20, 2004.

The teams went in opposite directions after that, with Ottawa enjoying a long run of success, including a trip to the 2007 Stanley Cup final, while Toronto made the postseason just once between 2006 and 2016.

The Leafs, who beat the Senators four times in the playoffs across a five-year stretch in the early 2000s, returned to the NHL postseason in 2017 — the last time the Senators made it — with a young core led by Matthews, Marner and Nylander.

The Senators’ rebuild, meanwhile, took a lot longer than expected, but finally gained this season. Ottawa captain Brady Tkachuk finally made his playoff debut in his seventh year.

“All year we’ve talked about committing to the process,” Senators coach Travis Green said. “It’s no different now.”

Toronto, which has one series victory in nine tries in the Matthews-Marner era, opened the scoring at 7:09 of the first period when Ekman-Larsson fired past Ullmark’s glove to send the home fans into a frenzy.

“The atmosphere was great,” Stolarz said. “Had goose bumps when you stepped on the ice and the crowd goes nuts. I think that propelled us.”

Senators defenseman Jake Sanderson cleared a puck off his goal line later in the period, but Marner took a stretch pass from Matthews moments later and roofed a shot with 7:42 left for a 2-0 lead.

Ottawa got on the board exactly four minutes later when Batherson was fastest to a rebound Stolarz was unable to smother.

The Maple Leafs' goalie stopped Tkachuk on a breakaway early in the second before Toronto's power play when to work when Tavares knocked in his own rebound at 4:07 to make it 3-1.

Toronto struck 3 seconds into a two-man advantage when Nylander ripped his team’s fourth goal on just 10 shots at 7:19.

Toronto scored on three of six opportunities with the man advantage.

“We took too many penalties, they scored on (them) and that’s the game,” Tkachuk said. “So that’s on us. We’ve got to be more disciplined.”

Fabian Zetterlund had a great opportunity on an Ottawa power play late in the period, but Stolarz was there to keep the score at 4-1 through 40 minutes.

“Timely saves are huge, especially in the playoffs,” Maple Leafs coach Craig Berube said. “They go a long way.”

Greig got the Senators back within two exactly four minutes into the third on a delayed penalty, but Rielly made it 5-2 just 45 seconds later on a shot that hit a Senators player in front.

Knies rounded out the scoring on another power play with 6:47 left to cap the scoring.

“We definitely have to stay out of the box, I’ll say that,” Green said. “Sometimes things (get) a little out of hand once in a while. I thought there was a couple calls that they did a good job selling, but it’s tough on the refs.

“But we can’t take that many penalties.”

OTT wins series 3-0