Dak Prescott’s hamstring injury diagnosis doesn’t look great.

According to a report from NFL Network, the Cowboys quarterback’s hamstring tendon is partially torn away from the bone (partial avulsion), and the recovery time from such an injury can be more than four weeks.

Prescott is now seeking further medical reports.

During an interview with 105.3 The Fan, Cowboys owner Jerry Jones said, “It’s likely we’ll put (Prescott) on IR and see how his rehab goes.”

Prescott’s injury occurred in the third quarter of Sunday’s 27-21 loss to the Falcons.

“I felt it when I got up from running. I can’t even say I felt the running. Maybe it was the tackle or something else,” Prescott said of the issue, according to the Cowboys team website. “When I got up I felt something but didn’t think it was much. It was a physical game and often you feel something else and then they disappear.”

Cooper Rush is expected to start for the Cowboys on Sunday when Dallas plays the Eagles at AT&T Stadium.

“Nothing really changes for us. Even though I spoke to Dak earlier, this is about the quarterback room. We always put all the time and energy into the quarterback Dak having the football,” Cowboys coach Mike McCarthy told reporters this week, according to ESPN. “Now it’s Cooper’s turn and Dak will be part of that process. We’re going to rally around him and make sure we do everything we can to make sure he’s prepared. We’ll just carry on as before.”

Prescott has thrown for 1,978 yards and 11 touchdowns for the Cowboys this season.

He had just signed a four-year, $240 million contract extension before the start of the season.