"This is a different one and I think something that I haven't dealt with before," Karlsson said. "First time I sat out, it was different than the second. Whether they were correlated to each other, we don't know. You can't really find that out.
"But I feel like I'm still healing the same way, and I'm still doing the things I need to do for my body to be as prepared as possible for when I do come back. And I feel like I've done that. It feels good, and again, hopefully I don't have to deal with this again."
Karlsson, whom the Sharks acquired from the Ottawa Senators in a blockbuster trade on Sept. 13, has 45 points (three goals, 42 assists) in 52 games this season.
"It's a big boost for our back end," forward Evander Kane said. "We've missed his skill set and poise with the puck and playmaking abilities back there. He looked good in practice, and hopefully it will be a good test run heading into the playoffs tonight."
Forward Timo Meier will not play against the Avalanche because of an injury, but DeBoer called him day to day.
"He would play if tonight was a playoff game," DeBoer said. "I think we're just being cautious with it. He's a little sore, but he's going to be OK."