The 24-year-old center scored his 55th goal of the season late in the second period, passing Rick Vaive to claim Toronto's single-season goal-scoring record. His 56th gave the Maple Leafs the victory in overtime and set the record for most goals by a U.S.-born player in a season.
"This was Auston's night,'' Toronto coach Sheldon Keefe said. "It's much deserved and to finish it with an exclamation point."
Matthews accomplished both feats in only 66 games, and he has netted 49 goals in his past 50 games alone.
Jimmy Carson (1987-88) and Kevin Stevens (1992-93) previously held the record for most goals by a U.S.-born player with 55.
Vaive's 54-goal mark, meanwhile, had stood for over 40 years, from the 1981-82 campaign (which was the highest-scoring season in modern NHL history). The 62-year-old former winger knew it was only a matter of time before Matthews came for his mantle.
"I'm happy for him, I really am," Vaive told ESPN. "I expected him to do it two years ago. He's a generational-type player. It's been 40 years that I had that record. I'm just glad that I'm around to see it."
Toronto's first overall pick in 2016, Matthews had 47 goals before the 2019-20 season was shut down due to COVID-19, and he scored 41 goals in the pandemic-shortened 56-game schedule last year.
Matthews scored his first goal on Thursday with a one-timer from the bottom of the circle to the left of goalie Scott Wedgewood after taking a pass back from Mark Giordano on a power play for a 2-1 lead with 1:02 left in the second period. The winner came when Matthews took a pass from William Nylander and was able to swipe the puck around Wedgewood in overtime.
Matthews emphatically pumped his right arm after the goal in the second period that broke the franchise record.
"I just saw the puck go in, and I was just so excited, honestly,'' he said. ''There really was not that much else to it. [Giordano] made a really nice pass, and he put it right in my wheelhouse, so I just tried to attack the puck, and I was able to sneak it in. So it was a lot of stuff going through my mind.''
Vaive was the first player in Leafs franchise history to score 50 goals, doing so three times in the 1980s. Gary Leeman (1989-90) and Dave Andreychuk (1993-94) were the only others to match Vaive with at least 50 goals, until Matthews crossed the threshold on March 31 against the Winnipeg Jets.
Matthews needed just 62 games to score his 50th goal, making it the fastest 50-goal season since 1995-96.
Now he has set a new benchmark in Toronto, one he could continue building on this year and maybe surpass in seasons to come.
"His skills are outrageous," Vaive said. "It's just crazy, how good he is with the puck and how good his shot is. I'm happy that a guy like him has done this, because it would have been different if it was someone who just happened to have a fluke year and did it [once], whereas he's a guy that you can count on probably to get there or close every single year."
Matthews continues to lead the NHL in goals and is on track to win the second consecutive Rocket Richard Trophy of his career. With 50 goals, the Edmonton Oilers' Leon Draisaitl has been Matthews' closest competition for the prize that goes to the league's leading goal scorer.
The Associated Press contributed to this story.