The 21-year-old, who became the most expensive American soccer player when he joined Chelsea in January 2019 for 64 million euros, has not played since the 1-1 draw against Brighton & Hove Albion on New Year's Day.

"I didn't take it as seriously as I think I should have. It was one of those you felt you could do a lot of things but you try to push it that one extra step and realise it's not ready yet," Pulisic told Chelsea's website.

"It was very tough and frustrating going through times like that. I underestimated it and tried to get back as soon as I could because I just wanted to play so bad.

"If anything, I've given myself a little more time to rest now and make sure that I'm 100% fit. I'd say I'm fully recovered and ready to go as soon as we get back."

Pulisic, named the US soccer federation's men's Player of the Year in December, has scored five goals in 16 league appearances this season.

The league is in discussions to restart the campaign next month after the government on Thursday opened the door for professional soccer to resume.

Chelsea were fourth in the league with 48 points from 29 games when the competition was suspended because of the pandemic.

Australian Associated Press