At 5-on-5, Karlsson, the best offensive defenseman in the NHL, paired with Marc-Edouard Vlasic, perhaps the best defensive defenseman in the League. In a 3-on-3 scrimmage, Karlsson skated with Brent Burns, the next-best offensive defenseman in the League, and forward Joe Pavelski.
"Nothing too shabby," Karlsson said.
[RELATED: Karlsson practices with Sharks for first time]
Burns hit Karlsson with a stretch pass, springing him on a breakaway. Karlsson didn't score. Still, as general manager Doug Wilson said, "It's not often you see a 150-foot breakout pass from D to D."
Practice ended with this: Karlsson raced ahead, dug out a puck down low and sent a pass across the low slot for Burns. Goal. Smile. Fist bump.
"When you've got [Burns] and Karlsson back there, it's a pretty fun style of play, for sure," Pavelski said.
Go ahead. Poke at their defense. Even the Sharks did themselves, good-naturedly. The unit of Burns, Karlsson and Pavelski followed the unit of Logan Couture, Evander Kane and Joe Thornton, and Kane said, "We were joking around that those first two 3-on-3 units didn't have any defensemen."
"I don't think [Pavelski] ever played that much defense before," coach Peter DeBoer said. "He was the only guy back. He's going to have to learn to skate backwards a little bit with those two."
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But seriously, Karlsson won the Norris Trophy as the best defenseman in the NHL in 2012 and 2015. Burns won it in 2017. Since 2011-12, when Karlsson won the Norris for the first time and Burns joined the Sharks, Karlsson has 447 points, Burns has 383, and no other NHL defenseman has more than 337. Wilson will tell you Vlasic remains underrated and should be a Norris candidate each season for his defense.
DeBoer has loads of options, making the Sharks hard to prepare for and match up against. At 5-on-5 or 4-on-4, he could put Karlsson with Vlasic and Burns with Justin Braun, giving each pair one offensive and one defensive defenseman.
"I felt like my offensive game today went through the roof," Vlasic said.
DeBoer could flip them, putting Karlsson with Braun, Burns with Vlasic, or put Karlsson, Burns and Vlasic on separate pairs, so each pair has one left- and one right-handed shot and one of the big three is always on the ice.
Need a goal? He could put Burns and Karlsson together.
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Need to protect a lead? He could reunite Vlasic and Braun, the Sharks' shutdown pair, or use Karlsson with anybody. Early in practice Wednesday, Pavelski skated down the right wing. When he saw he was facing Karlsson, he broke into a big grin.
And then Karlsson knocked the puck off his stick.
"What I love about Erik's game, everybody looks at the offense, but he's an exceptional defensive player too," DeBoer said. "So I think you can use him in every situation.
"There's very few players in the world that I would term that you can use in the last minute of games when you're up or your down, to shut down the other teams' best players, to create offense when you're from behind. He's one of those guys. He has those type of tools. So we're going to use him in a lot of different ways."
The Sharks power play has been disappointing for two seasons, 25th in the NHL in 2016-17 (16.7 percent) and 16th last season (20.6 percent). That should change. Karlsson is more of a quarterback, Burns more of a shooter. If you think they're fun together 3-on-3, imagine them together 5-on-3.
Video: OTT@DAL: Karlsson nets OT winner on breakaway
"When you get to play with a guy that can skate like that, make plays, confident with the puck, it's great," Burns said.
There is only so much ice time to distribute. Karlsson averaged 26:44 last season, third in the NHL. Burns averaged 25:15, 10th in the League. Vlasic averaged 22:33, Braun 21:20, Brenden Dillon 17:19 and Joakim Ryan 16:45.
"Nice problem to have from a coaching point of view, but we have a lot of quality defensemen," DeBoer said. "We're going to have to try to maximize all of them. When you play on a good team, everyone's got to sacrifice a little bit of ice time in order to do that. I think the guys understand that."
It isn't necessarily a bad thing. When Karlsson and Burns jump into the play, they'll have fresher legs.
"I played on the [Swedish] national team for a long time now," Karlsson said. "I've done one Olympics, one World Cup, where everyone is an extremely good player, and that's something that I always look forward to. It was something that I always enjoyed, and I think that challenges you to do things in a different way sometimes.
"And I'm looking forward to that here as well. I'm coming into a group that has been together for a long time, that has good chemistry. It's my job to try to fit in as good as I possibly can to that group, and whatever that might be, to help contribute to win hockey games, I'm going to do everything I can."