The Cowboys will be without rookie linebacker DeMarvion Overshown not only in Week 1 against the Giants but for much longer.

Overshown tore his ACL on Saturday night against the Seahawks, according to the Dallas Morning news.

The rookie had been scheduled to undergo an MRI Sunday.

Overshown, a third-round pick, hurt himself tackling Seahawks running back Zach Charbonnet during Dallas’ 22-14 win.

It looked like a routine play, but Overshown grabbed at his knee after trying to get up.

Exactly where Overshown would have landed on the depth chart isn’t clear, but based on reports from training camp he was in line to have a role on the defense.

He made six tackles in the preseason opener, with three more before getting hurt Saturday.

“We talked about him seems like almost every other day,” Cowboys coach Mike McCarthy told reporters, according to Sports Illustrated’s Cowboys Country. “He was climbing the charts … Really has excellent command for a young player, young linebacker.

“So, just hopeful.”

Though the trio of Leighton Vander Esch, Damone Clark and Jabril Cox figures to start in the Cowboys’ 4-3 defense, Overshown might have gotten heavy rotation snaps.

Late Saturday night, Overshown tweeted “Still Blessed” with a praying hands emoji attached.

A video surfaced displaying Overshown walking on his own power shortly following the injury.

“You never want to see any of your guys get hurt,” McCarthy said. “That’s what is so tough about these games. We had a couple young guys go down, and you just say your prayers and hopefully, the [MRI] points in the right direction.”