Cowboys quarterback Dak Prescott's initial diagnosis is that the hamstring tendon has partially torn away from the bone

Dak Prescott's hamstring injury could potentially keep him out longer than originally hoped.

Prescott's initial diagnosis is that his hamstring tendon has partially torn from the bone, known as a partial avulsion, NFL Network's Jane Slater reported Wednesday.

Recovery time from such an injury is generally more than four weeks, according to Slater. Prescott is currently seeking further opinions on his injury, Slater added.

Cowboys owner Jerry Jones said Tuesday that Prescott would likely go on injured reserve, which would sideline him for at least four weeks.

Cooper Rush is expected to start for Dallas against the Philadelphia Eagles on Sunday, but if Prescott is out for more than a month, it's worth keeping an eye on whether Trey Lance, No. 3 on the depth chart, gets a run.

Prescott, who agreed to a four-year extension worth $240 million this season, has completed 64.7% of his passes for 11 touchdowns and eight interceptions this season.

Dallas (3-5) hosts Philadelphia (6-2) on Sunday at 4:25 p.m. ET.