Lindegaard sustained the problem in Saturday's Premier League game at home to Norwich but was determined to complete the 90 minutes.
He kept a clean sheet in United's 2-0 victory but could not shake off the knock and has had to withdraw from the Denmark squad for Euro 2012 qualifiers against Cyprus and Portugal.
The 27-year-old will now return to United's Carrington training ground to undergo intensive treatment and is facing a race against time to be fit for the clash with their fierce rivals at Anfield on October 15.
"I got a stamp on my ankle at the start of the match on Saturday and should have come off," Lindegaard said in the Daily Star.
"I chose to carry on and paid the price. And although I have to sit on my couch with my leg up now, it was incredibly important for me to play.
"The medical staff at United believe that the earliest I could train again is next week."
Lindegaard has been vying for the No.1 spot this season with summer signing David de Gea, who now looks set to line up between the posts against Liverpool.