He did Friday, when his three third-period points (one goal, two assists) helped Toronto defeat the Detroit Red Wings 3-2.
And he did Sunday, producing a highlight-reel finish in front of about 100 friends and family to go with an earlier assist.
His contributions in Toronto's two-game series: two goals, three assists, the extension of his team-record 17-game point streak to start a season and a hand in both game-winning goals for a team that flew home winners of four straight.
In the process, his impact cut much deeper than that.
He was a celebrity here, and he embraced every delectable second of it, whether it was signing autographs for a throng lined up for more than two downtown blocks or being named player of the game against the Red Wings in front of Eva Altelius, his 73-year-old maternal grandmother who had never seen William play live.
And he did all of it in pure "Willy Styles" fashion, as his teammates call him.
Being calm, being cool. being collected. That's the William Nylander way. And that didn't change despite the expectations of the Swedish public.
"Pressure? Willy? I don't think Willy ever feels pressure," teammate Mitchell Marner said. "That guy's mellow all the time.
"He's chillin'."
He certainly was during his postgame press conference.
"Walking around with my buddies and then playing an NHL game, it's been weird, but it's been lots of fun," Nylander said.
So much so that he'd like to repeat the experience, game-winner and all.
"It was special for me to do that in overtime, but I wish we didn't go to OT," he said. "It's been a blast. I love being here and hopefully we can do it again sometime."
Keefe marveled at how the 27-year-old handled himself all week, on the ice and off, what with being pulled in so many different directions.
"He had a full plate here, probably more than anyone on these four teams," Keefe said, referring to Global Series participants Toronto, Detroit, Minnesota and the Ottawa Senators. "To be able to do that and still spend time with his family and still put on a show on the ice and still make the impact that he did is tremendous.
"Thrilled for him."
So is Sweden hockey legend Mats Sundin, whose 420 goals and 987 points are each first in Maple Leafs history.
"William is playing as well as he ever has," Sundin said. "It's great to see."
Sundin was in the building Sunday, dropping the puck as part of the ceremonial opening face-off and receiving a well-deserved standing ovation. And then, about three hours later, he, daughter Bonnie and sons Julian and Nathanael were on hand when Nylander decided to end the game with a victory.
Rielly had an ice-level view of the entire thing. What was going through his mind at the time?
"Just watching him dance, do his thing," Rielly said.
"You kind of had a feeling that going into overtime he might be the guy. And for him to come through, he just kind of has a knack for those things."
He certainly did this past week. And it made for a visit people in this city won't soon forget.
