With the team's Thanksgiving Day showdown against the Chargers unfolding just four days later, Rapoport was told Lee could miss both affairs.
It's an ugly setback for Dallas, already without suspended star running back Ezekiel Elliott and possibly without stalwart left tackle Tyron Smith, who is still dealing with a groin injury.
Smith's absence was a downright disaster for the 'Boys against Atlanta, with Chaz Green stepping into the left tackle spot and allowing five of Adrian Clayborn's six sacks on quarterback Dak Prescott.
Lee is equally important to a defense that statistically -- and in real life -- isn't remotely the same without his leadership and rare athleticism on the field.
Sitting at 5-4, Dallas can hardly afford to fall another game behind the 8-1 Eagles, a team ready to run away with the NFC East crown barring a major turn of events over the next seven weeks.