TORONTO -- The Ottawa Senators haven't had much to get excited about this season.
Stuck in neutral down 5-1 late in the second period against the high-flying Toronto Maple Leafs, it looked like Monday was going to be another forgettable night for a franchise still in the midst of a painful rebuild.
Until it didn't.
Evgenii Dadonov tied the game late in the third period before scoring the winner on a breakaway at 2:19 of overtime as Ottawa roared back from a four-goal deficit to stun Toronto 6-5.
After blocking a Morgan Rielly chance in the crease with Senators netminder Marcus Hogberg completely out of position in the extra period, Dadonov sped the other way and buried his sixth goal of the season upstairs on Frederik Andersen.
"It's hockey ... anything can happen," Dadonov said of the incredible turn of events. "We didn't stop playing."
Connor Brown and Nick Paul, with a goal and an assist each, Drake Batherson and Artem Zub, with his first in the NHL, also scored for gutsy Ottawa (4-12-1). Hogberg stopped 33 shots for the Senators, who face the Leafs again Wednesday and Thursday at Scotiabank Arena.
"Give the guys credit for staying in the fight," Ottawa head coach D.J. Smith said. "(Hogberg) gave us every chance. I thought we hung him out for a couple periods. We just didn't have our legs.
"We were flat, we didn't make many plays, but we found a way.'
Auston Matthews scored twice and added an assist for Toronto (11-3-2), while Joe Thornton, with a goal and an assist in his return from injury, Travis Boyd and Pierre Engvall provided the rest of the offence. Andersen finished with 25 saves as the Leafs dropped their second straight at home following Saturday's 2-1 loss to the Montreal Canadiens.
"Sloppiness is creeping into our game," said Leafs head coach Sheldon Keefe, who appeared to shake his head in disgust at the conclusion of a video conference call with reporters. "It wasn't everybody, but enough guys gave the game to them.
"What we had against us is sloppy play ... that led to us playing more in our end than we had to."
But give credit to those pesky Senators.
Ottawa stormed back to force extra time with four straight goals, including Dadonov's batted effort out of mid-air with 2:01 left in regulation and Hogberg on the bench for an extra attacker.
Dadonov, who now has five goals in his last five games after scoring just once in his first 12 outings with the team he joined in free agency, then buried another after stepping in front of that Rielly shot in the crease in OT.
"It was quite the play," Batherson said of the sequence. "He's hot right now. We love seeing it."
"Sometimes you get in position behind the goalie," Dadonov added with a smile. "So you try and stop some shots."
Matthews scored his second of the night and league-best 13th goal with just under a minute left in the second on a 5-on-3 power play to give the Leafs a 5-1 lead, but Ottawa got that one back shorthanded with nine seconds left in the period when Paul took advantage of a careless turnover by Toronto captain John Tavares for his third.
Zub then scored his first in the NHL coming out of the penalty box on a beautiful deke to the forehand 41 seconds into the third to get Ottawa within two at 5-3.
Toronto's Zach Hyman was assessed a double minor for high-sticking on Thomas Chabot, but the Leafs had the best chance when Hogberg stopped Ilya Mikheyev.
The Senators would eventually get within one, however, moments after the penalty expired when Brown, who was traded from Toronto to Ottawa in the summer of 2019, scored his third at 5:52.
"When we got the fourth one you could see the bench go, 'Wow, we're in this,'" Smith said. "It's hard to believe when you're down the way we were. All of a sudden we found our legs.
"That's what momentum does -- it gives you energy."
Hogberg made a nice stop on Hyman with under seven minutes to go to keep it at 5-4, setting the stage for Dadonov's equalizer and overtime heroics.
"Unbelievable," Batherson said. "So happy for everyone. Comebacks like that, those are the best wins."
Following that loss to Montreal that saw both their four-game winning streak and nine-game point streak (8-0-1) snapped, the Leafs were shot out of a cannon early in Monday's first.
Matthews scored his 12th goal in 14 games this season when he took a feed from Thornton at 6:32. Andersen stoned Chabot at the other end as the Senators started to show life, but Toronto broke the other way, with Boyd firing home his second at 10:29.
The last-place Senators, who won back-to-back games for the first time since March after beating the Winnipeg Jets 2-1 on Saturday, cut the deficit in half 2:11 later. Tim Stutzle -- the No. 3 pick in the 2020 NHL draft -- knocked down a clearing attempt before finding Batherson to make it 2-1 as the Leafs held a 13-3 edge in shots through 20 minutes.
Toronto kept coming in the second, with Engvall scoring his first off a stretch pass from T.J. Brodie and another slick feed from Alexander Kerfoot on an odd-man rush at 1:49.
Brady Tkachuk got mixed up with Andersen and Leafs defenceman Jake Muzzin. Tkachuk and Muzzin, who flipped a puck at the Ottawa winger's older brother, Matthew, following a Toronto victory in Calgary against the Flames last month, dropped the gloves in a short, but spirited fight.
Back on Toronto's top line with Matthews and Mitch Marner after missing 10 games with a fractured rib suffered Jan. 20, the 41-year-old Thornton scored his second at 9:51 to make it 4-1 after Senators blue-liner Mike Reilly needlessly gave the puck away.
Matthews would bag his second late in the period before Ottawa started to turn things around with Paul's short-handed effort that materialized out of nothing.
"A couple of careless plays," Matthew said. "They challenged us and we didn't really respond. We definitely blew this one."
The Senators, meanwhile, felt they deserved some good fortune after suffering through an 0-8-1 stretch earlier this season and ending a four-game slide Saturday in Winnipeg.
"There's been a lot of nights I felt we maybe played well or played better than the other team and didn't win," Smith said. "Tonight's not one of those nights, but it was due to come our way."
