FRISCO, Texas -- Dallas Cowboys linebacker Leighton Vander Esch will undergo surgery on his broken collarbone and be placed on the injured reserve/return list, executive vice president Stephen Jones confirmed Monday on 105.3 The Fan in Dallas.

Jones also said tight end Blake Jarwin suffered a torn ACL in his right knee in Sunday night's season-opening loss to the Los Angeles Rams.

"Obviously a tough loss," Jones said.

Vander Esch, who will have the surgery Tuesday, is expected to miss six to eight weeks, according to a source. The collarbone will be repaired with a plate and screws, similar to the surgery former quarterback Tony Romo had on his broken left collarbone in 2015.

Vander Esch suffered the injury in the first quarter and was replaced by Joe Thomas. Romo missed nine weeks (eight games) in 2015 with his collarbone injury and suffered a re-break in his return against the Carolina Panthers on Thanksgiving and was done for the season.

Vander Esch, who made the Pro Bowl as a rookie in 2018, missed seven games last season with a neck injury that eventually required a minimally invasive procedure in the offseason to fix. But he said in training camp that he has had no issues with his neck.

With Vander Esch out and Sean Lee missing at least the next two games on injured reserve with a pelvis issue, the Cowboys have four linebackers on the 53-man roster. Luke Gifford, who was inactive against the Rams, has been working back from a hamstring strain. It is possible the Cowboys could call up rookie Francis Bernard from the practice squad.

Vander Esch and Jarwin's injuries were not the only ones of significance for the Cowboys. Backup offensive tackle Cameron Erving suffered a sprained medial collateral ligament in his left knee and could miss a few weeks, according to a source.