Urlacher told WFLD-TV on Tuesday that doctors said he could be out "two to four weeks, three, could be four."
The eight-time Pro Bowl player is in the final year of his contract, leading to speculation that he could have played his last down in the Windy City. Urlacher admitted the possibility but wasn't ready to be nostalgic.
"I do not think that's going to happen," he told the TV station. "But, if it does, I have had a really good and long career, so I would be sad, but I would not be crushed."
The 35-year-old is in his 13th NFL season, playing all of his professional snaps for the Bears. He said with Chicago in line to make the playoffs, he is "100 percent" sure he would play in a potential playoff game.
The Bears were 7-8 in the 15 games Urlacher missed in 2009 and 0-7 without him in 2004.
At 8-4 this season, Chicago has the inside track to the playoffs but can't afford another collapse with three road games (Minnesota, Detroit, Arizona) and a home rematch with the Green Bay Packers still on the slate.
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