The Broncos signed veteran inside linebacker Joe Schobert and activated outside linebacker Randy Gregory and right tackle Billy Turner from the physically unable to perform list before practice Monday.

Schobert, who worked out for the Broncos early in camp, was signed as insurance for Jonas Griffith.

Griffith sustained a left elbow injury in Saturday’s win over Dallas. Griffith will not require surgery and remains possible to play in Week 1 at Seattle. Coach Nathaniel Hackett gave a timetable of 4-6 weeks for Griffith.

The Broncos open the season four weeks from tonight.

Gregory (shoulder) and Turner (knee) are eligible to participate in walk-throughs and full practice now that they are no longer on the PUP list. Both missed the entirety of the offseason program.

Gregory said the decision to have surgery after signing with the Broncos was “difficult. It was something I was dealing with for two, maybe three years and it got to the point where it was hindering my play. It was important to do it long-term for the team. I’m glad we got it taken care of and it’s in the past.”

Turner doesn’t know if he will work at other positions besides right tackle.

As for playing in Week 1, Turner said: “Am I mentally ready and prepared? That’s what these next four weeks are for me, getting to the point where I feel I’m ready to go on the field and play a football game for 60 minutes.”

The Broncos waived/injured guard Ben Braden, who sustained a back injury last Tuesday.

Schobert (6-foot-1, 240 pounds) has played in 93 games (80 starts) for Cleveland, Jacksonville and Pittsburgh, totaling 647 tackles, 11 sacks and 10 interceptions. He entered the league as a fourth-round pick by the Browns in 2016.

Hackett said guard Netane Muti recently had knee surgery and will be sidelined a few more weeks.