The forward and Avalanche captain has not played this season after having knee surgery in October. At the time of the surgery, Landeskog was expected to be sidelined 12 weeks.
"I still thought I'd be fine, ready to go after the summer (2022)," Landeskog said Thursday, prior to the Avalanche defeating the Winnipeg Jets 4-2. "Obviously a very short summer (winning the Stanley Cup). I realized fairly quickly that things had gotten worse. … I thought I was going to be able to play the second half of the season. We've given it our best shot and it just hasn't worked out. Moving forward we continue to explore options. But I felt like this was the decision I had to make at this point for everybody involved and for my teammates and myself."
Landeskog also had knee surgery on March 21, 2022. He missed 23 games but came back to help Colorado win the Stanley Cup, playing 20 playoff games, and had 22 points (11 goals, 11 assists) and led Colorado with a plus-15 rating. Landeskog had surgery on his quad during the 2020 Stanley Cup Playoffs.
"The timeline goes back to the bubble 2020," he said. "Kind of a freak accident that happens there. Never had any knee issues before that. One thing led to the next and it just sort of progressively got worse over that next year. Start of [last] season it started bugging me on a daily basis. It got worse and worse up until the point that we got the first surgery. At that point I didn't really realize the complexity of the injury and how one injury can, obviously it compensates."
Landeskog said he wasn't sure if he would have another surgery.
"I think it's a big decision, so it needs a lot of doing as much homework as I can on different options," he said. "But we haven't gotten to the point yet where I know exactly what that would mean. But nonetheless, I'd like to start progressing, moving forward as fast as I can and as soon as possible. So, we'll see when that is. … For me, it's been a long road up to this point, but I'm hopeful and optimistic and confident that eventually we'll come out on the other side of this. But we haven't quite got past it yet obviously."
One thing Landeskog was certain of was that he will play again.
"I'm confident in that," he said. "When? I don't know. You try and take it one step at a time. This is no different than going into a new season, essentially. Where you start with training camp and you go from there. This is the same thing. I'm trying not to look too far ahead. But I'm confident, and like I said, we'll get through this."
Avalanche forward Nathan MacKinnon said Landeskog and his teammates had known the news for a while.
"He didn't decide today," MacKinnon said. "He didn't wake up and decide he's going to be done for the year. It's unfortunate. It kills us, for sure. So hopefully we can survive without him."
Landeskog, 30, has 571 points (248 goals, 323 assists) in 738 regular-season games, all with Colorado, and 67 points (27 goals, 40 assists) in 69 playoff games.
"It's a huge blow," Colorado coach Jared Bednar said. "I mean, he's our captain, one of the top players in the world. But we've been without him. You have to prepare to go without him until he says he's good, and obviously he can't get to the point where he feels like he's going to be able to go and help. So he's going to explore other options."
The Avalanche (50-24-7), who play the Nashville Predators on Friday (8 p.m. ET; BSSO, ALT, ESPN+, SN NOW) will clinch the Central Division with a win. They will have home-ice advantage in the first round of the playoffs, which begin Monday.
"There's a lot of champions in there," Landeskog said. "Majority of the guys were there (last season), and they know what to expect. I think that's the advantage you have after having gone through it, is you know what to expect every step of the way. Will things be difficult and hard? Absolutely, as it should be.
Said Avalanche forward Mikko Rantanen: "He's a warrior. It's mentally tough to go through a stretch like this where you can't play the game you love, can't be around the guys as much as you would want. But we still see him every day. He's in good spirits, which is good to see. We try to support him as well."
NHL.com independent correspondent Ryan Boulding contributed to this report
