For Methot, at least, this is nothing new.
He had the same assignment when he was playing for the London Knights of the Ontario Hockey League at the 2005 MasterCard Memorial Cup, where the Knights defeated Crosby's Rimouski Oceanic of the Quebec Major Junior Hockey League once in the preliminary round and again in the final.
Methot and defense partner Dan Girardi (now of the New York Rangers) combined with forward Brandon Prust (now of the Montreal Canadiens) to try to blanket Crosby in the tournament. After allowing Crosby to get a goal and an assist in a 4-3 preliminary-round win, the Knights shut out the Oceanic 4-0 in the championship.
"Probably not a lot has changed [since then]," Crosby said Tuesday with a laugh. "We're older, that's about it."
Perhaps their respective roles haven't changed, but Methot did find one area that is different in the matchup.
"In a sense the tables have turned a little bit," Methot said Wednesday. "He's playing on the powerhouse team now and we're kind of the underdogs. He's got some great players to play with. Not to say he didn't have it then, but he's got a better supporting staff here."
Methot and Karlsson were on the ice nearly every time Crosby jumped over the boards with linemates Pascal Dupuis and Chris Kunitz in Game 3 of their current playoff series Sunday. Though Crosby did have a breakaway early in the second period that was stopped by Senators goalie Craig Anderson, Methot, Karlsson and the forward line of Kyle Turris, Daniel Alfredsson and Jakob Silfverberg did a good job of shutting down the Penguins' big line in a 2-1, double-overtime win.
"I don't really think about that a whole lot," Crosby said of rekindling his matchup against Methot. "But as you play you run into guys that you played against before, and it's kind of funny to see guys that you're matching up against now. [I] probably never would have thought I'd play in the playoffs against him in the second round."
Senators coach Paul MacLean said he has liked what he's seen from his shutdown pairing, but he didn't want to give them too much credit too soon.
"They both skate very well, and I thought they were able to maintain a gap that was sufficient enough to stall them," MacLean said. "But I still think [Crosby] got some chances, so I'm not sure if they stopped him or he stopped himself, or a combination of all of them, or was it just Craig Anderson who stopped him?"
The relative success Methot and Karlsson had in Game 3 against Crosby might be a one off, but it will need to continue in Game 4 on Wednesday night (7:30 p.m. ET; NBCSN, CBC, RDS) and beyond if the Senators, down 2-1 in the best-of-7 series, are to have any chance of pulling off an upset against the top seed in the East.
"I love that kind of challenge," Methot said. "For me, that's what I get up for and that's the reason why I play this game."
The Senators' run to the second round has allowed a spotlight to shine on Methot, acquired in an offseason trade with the Columbus Blue Jackets and enjoying his first taste of Stanley Cup Playoff success getting to play in his hometown.
Methot had never won a playoff game before this season, and a big reason the Senators are still alive is because of his hard, physical and defensively sound brand of hockey.
For someone who played four playoff games before this season, Methot is looking like he was built for this time of year.
"I had a little bit of a taste in Columbus when we played against Detroit for the one round, but it wasn't the same," Methot said. "We didn't win a game. We had a hard time, and for a lot of us it was kind of like a deer in the headlights. But now I've been able to soak it in, and being in my hometown it's been really cool."
The people in his hometown, and Crosby, already knew about Methot's game, but now the rest of the hockey world is getting a glimpse of his shutdown style.
A star is perhaps in the making.
"He's getting an opportunity to play in the playoffs and he's trying to relish it and enjoy it," MacLean said. "You can almost make a career just by playing good in the playoffs."