William Karlsson of the Golden Knights starts the season as a reserve player

The Golden Knights confirmed their season-opening roster ahead of Monday's deadline at 5:00 p.m. EST. Since Karlsson is not on the list, that means he was placed on IR at the start of the season.

Karlsson suffered an injury during training camp and his status has been uncertain since the opening preseason game. The type of injury or its severity is not yet known to the public at this time.

Karlsson is coming off his best season in years, scoring 30 goals and 30 assists for 60 points in 70 games for the Golden Knights. It marks the first time Karlsson has reached both the 30-goal and 60-point marks in a season since Las Vegas' inaugural season in 2017-18, in which he scored 43 goals and 78 points.

However, Karlsson's performance declined in the playoffs, as he only had two assists in seven games as the Golden Knights were eliminated in the first round by the Dallas Stars.

Originally a second-round pick of the Anaheim Ducks in the 2011 NHL Draft, Karlsson made his NHL debut in the 2014–15 season before being traded to the Columbus Blue Jackets at the trade deadline of that year as part of the return of James Wisniewski. He then spent parts of three seasons in Columbus before being selected by the Golden Knights in the expansion draft. He is now entering his eighth season in Vegas, where he won a Lady Byng Trophy in 2018 and a Stanley Cup in 2023.

Karlsson enters the sixth season of an eight-year contract he signed with the Golden Knights in the summer of 2019 on a $5.9 million contract.

The Golden Knights will look to start their season on the right foot when they host the Colorado Avalanche in Vegas on Wednesday at 10 p.m. EST.