The Dallas Cowboys lost a critical game against the Atlanta Falcons in Week 9 to drop to 3-5 on the season. They also lost their starting quarterback during that contest.

Dak Prescott suffered an injury that kept him out for most of the fourth quarter in Dallas' 27-21 defeat. It wasn't originally believed to be a big deal, but the malady could end up sidelining the team's top signal-caller long-term as the Cowboys look to scratch their way into the postseason mix.

How long might Prescott be out, and what is Dallas' contingency plan if he can't play? Here's what to know about the quarterback's injury and his timeline to return from it.

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Dak Prescott injury update

Cowboys fans were dealt more bad news on Wednesday, as it was revealed that Prescott is dealing with a partial avulsion of his right hamstring. That would likely keep him out for longer than four weeks, per ESPN's Todd Archer.

The Cowboys haven't officially placed Prescott on IR as of Friday, but they are planning to do so before their Week 10 game against the Philadelphia Eagles. NFL Network's Jane Slater reports that the team originally had "a reluctance" to do that as the quarterback sought other opinions about how to deal with his injured hamstring.

Prescott had an MRI on his leg on Monday. That revealed that the injury "was worse than initially feared," per NFL Network's Ian Rapoport. It was expected to keep him out "multiple weeks" with an IR stint possible.

"It's something I’ve never felt," Prescott said while describing the injury. "I saw the medical team and asked could I make it worse. At that point they said I wouldn’t be able to protect myself and made the call to hold me out."

The quarterback told reporters after the game he wasn't sure if he suffered the injury while running or while being tackled.

What is a hamstring avulsion?

There are three types of hamstring strains, according to the American Academy of Orthopaedic Surgeons. They are as follows:

• A pull

• A partial tear

• A complete tear

A hamstring avulsion is a complete tear during which the tendon rips off the bone entirely. That makes it the most severe kind of hamstring injury.

In Prescott's case, he is dealing with a partial avulsion, which means only part of the tendon pulled away from the bone. Still, that could set him up with a long recovery, pending the overall severity of the tear.

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How long is Dak Prescott out?

Prescott is out for at least four weeks because of his injury. The Cowboys are planning to put him on IR, as the team's vice president Stephen Jones outlined Friday on 105.3 The Fan.

"I think it's probably no way he can be back in the four-week timeframe, so we'll put him over there and we'll have that roster spot to use in terms of the next four weeks and go from there," Jones said, as transcribed by ESPN. "Obviously a tough, tough situation, losing him for that period time, but we're going to do what's in the best interest of Dak and right now I don't think anyone knows whether it'll be four weeks, six weeks or the season. We'll just have to continue to monitor that and see where it takes us."

That makes Prescott's earliest potential return date the team's Week 14 game against the Cincinnati Bengals.

Originally, Prescott was expected to miss "multiple weeks" That said, Slater reported there was "a reluctance" to put Prescott on IR as he weighed options to repair the injury. As such, the team waited as long as it could to make any official determination about a timeline for the NFL's highest-paid player to return.

The American Academy of Orthopaedic Surgeons says that a Grade 3 hamstring strain can take "months" to heal. It isn't clear if Prescott's partial avulsion falls into that category, but it appears that he will at least be out until December – and possibly longer, especially if the 3-5 Cowboys struggle during his absence.

Who is the Cowboys backup QB?

Cooper Rush is Dallas' backup quarterback. The soon-to-be 31-year-old was signed by the Cowboys as an undrafted free agent out of Central Michigan in 2017 and has spent almost his entire career in Dallas.

Rush has a 5-1 record as a starting quarterback and has completed 60% of his career passes for 1,786 yards, nine touchdowns and six interceptions. He last started a game in 2022, when he went 4-1 over a five-game stretch filling in for Prescott.

Rush has completed 22 of 39 passes (56.4%) for 167 yards, one touchdown and one interception in limited action during the 2024 season.

COWBOYS DEPTH CHART: More to know about Dallas' plans after Dak Prescott injury

Cowboys QB depth chart

The Cowboys have three quarterbacks on the 53-man roster and practice squad, including Prescott. Here's how they stack up on the team's depth chart:

1. Dak Prescott

2. Cooper Rush

3. Trey Lance

Lance was the No. 3 overall pick of the San Francisco 49ers in the 2021 NFL Draft, so he remains a potential-packed prospect at just 24 years old. If Rush struggles or the Cowboys fall out of contention, they could give the third-stringer a chance to showcase his talents as he prepares to hit free agency.

Dallas could also sign a fourth quarterback to the practice squad to serve as depth while Prescott is out of action.

This article originally appeared on USA TODAY: How long is Dak Prescott out? Hamstring avulsion sets murky timeline