Chicago Blackhawks star Jonathan Toews on Wednesday opened up about why he missed the entire 2020-21 season.

Toews, the 33-year-old center who has won three Stanley Cups with the Blackhawks, explained he had been dealing with chronic immune response syndrome. He talked about the illness in a video.

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"I just think there’s a lot of things that just kind of piled up where my body just fell apart," he said. "I just couldn’t quite recover and my immune system was reacting to everything, any kind of stress — anything that I would do throughout the day there was always kind of that stress response, so it took some time."

Toews said he started to feel "drained and lethargic" in December and the team ruled him out indefinitely.

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"I learned a lot about just the stress I put on my body over the years and appreciate all the support. A lot of people were worried, and I definitely felt bad to a certain degree that people were that worried that they thought it was really serious. But in the back of my mind, I knew I’d get through it. It was just a matter of time," Toews said.

In the video Toews appeared to be back at the facility and on the ice skating rink but it was unclear when it was shot.

Toews is one of the best players the Blackhawks have had in recent memory. He has scored 345 goals and collected 815 points in 13 seasons with Chicago. He was the 2010 Conn Smythe Trophy winner – which is given to the most outstanding player of the Stanley Cup Final. He also won the Selke Trophy in 2013 as the top defensive forward.

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He still has two years left on his contract. He said he plans to play for the Blackhawks next season.

The Associated Press contributed to this report.