Prescott sustained a partial avulsion of his right hamstring in Sunday's loss to Atlanta, and his best-case recovery timetable is 4-to-6 weeks, Jane Slater of NFL Network reports.
Prescott is expected to be placed on injured reserve as a result, but the Cowboys have yet to make such a transaction as they seek varying opinions on how to proceed with his rehab. Rest and icing the region are the likely routes to take, but there's also a possibility that he'll require surgery, depending on the grade of the injury. Cooper Rush will step in for Prescott as Dallas' starter for as long as the latter is sidelined, while Trey Lance will be active on game days as the backup quarterback.