The 49ers open the practice window for WR Christian Kirk

SANTA CLARA, Calif. (AP) — The San Francisco 49ers opened the 21-day practice window for receiver Christian Kirk on Thursday, giving the team another possible option to bolster an injury-filled position group.

Kirk practiced on a limited basis for the first time since hurting his calf in the first training camp practice in July. Kirk began the season on injured reserve and finally was able to get back on the field with his teammates after what coach Kyle Shanahan described as an "awesome weekend" in his recovery.

"Just felt like I kind of got over that hump and felt like myself again," Kirk said. "The body started to respond to the training and the recovery and whatnot. Just wanted to communicate that to them, and tell them that I was ready to go, and get back out there. So, excited to get out there. It's obviously been a while, and just ready to attack this week."

The move comes with the 49ers (5-0) missing injured receivers Ricky Pearsall, De'Zhaun Stribling and Demarcus Robinson for time already and now Deebo Samuel out for at least a few weeks after hurting his hamstring last weekend in Seattle. Shanahan said he doesn't expect Samuel back until the first game following the bye Nov. 8 at the earliest.

No. 1 receiver Mike Evans also has been dealing with two broken ribs and now has soreness in his Achilles that kept him out of practice.

The only healthy receivers at practice on the 53-man roster were Brandin Cooks, Jordan Watkins and Jacob Cowing as the team prepares for a game Monday night against Washington before Kirk jumped right in.

"It's like riding a bike," he said. "I've been doing it for a while, and so, for me, it's just getting back out there, getting integrated with the guys. Obviously, it's been hard not being out there, but been really cool to watch day in and day out how this team comes to work every single day, and for it to be able to carry over on Sundays. I'm just excited to get in the mix, and hopefully, provide some production to help us win some more games."

Kirk signed a one-year, $3 million deal with San Francisco in free agency in March. The 29-year-old Kirk has 432 catches for 5,415 yards and 30 touchdowns in eight seasons with Arizona, Jacksonville and Houston.

He missed 18 games the past three seasons with Jacksonville and Houston with injuries to his groin, collarbone and hamstring and was frustrated to be dealing with another injury with his new team.

"Anytime you go to a new organization, a new team, no matter what you've done, you want to prove yourself, and that's just how I felt," Kirk said. "I've just wanted to go out there, obviously, play with these guys. ... But to just be able to get out there and prove to them that I'm worthy to be a teammate and to be able to help win football games here. For me, it's been hard, but it's all about just how you approach every day and control what you can control."

The 49ers made two other roster moves on Thursday, promoting defensive lineman Ogbo Okoronkwo from the practice squad back to the active roster to fill a spot vacated by the one-game suspension of linebacker Dre Greenlaw. Linebacker Eugene Asante was signed to the practice squad for more depth at the position with Greenlaw and Garret Wallow (hamstring) out this week.

Defensive end Nick Bosa (calf) didn't practice Thursday, but Shanahan said there's a chance he could return this week after missing the past three games.

Defensive tackle Gracen Halton (quadriceps), James Thompson Jr. (ankle) and safety S Marques Sigle (ankle) also were out of practice.

Fullback Kyle Juszczyk was limited after missing last week's game with a knee injury. Right tackle Colton McKivitz (illness) and cornerback Upton Stout (shoulder) were also limited.