SANTA CLARA, Calif. -- After dealing with plenty of bad injury news during the season's first eight weeks, the San Francisco 49ers are finally closer to full strength.

Despite losing cornerback Jason Verrett to a season-ending left Achilles tear in Wednesday's practice, the Niners got plenty of good news on the injury front Friday, as they will welcome back eight players who missed San Francisco's latest game -- a 31-14 win over the Los Angeles Rams on Oct. 30 -- because of injuries.

Among the players set to play Sunday night against the Los Angeles Chargers are wide receivers Deebo Samuel (hamstring) and Jauan Jennings (hamstring), fullback Kyle Juszczyk (finger) and linebacker Dre Greenlaw (calf). Four players -- running back Elijah Mitchell, linebacker Azeez Al-Shaair, offensive lineman Colton McKivitz and defensive end Jordan Willis -- will all return from knee injuries that landed them on injured reserve, according to coach Kyle Shanahan.

The Niners have three open roster spots and will get a fourth when they place Verrett on injured reserve, a move that is expected to happen in the next 24 hours.

Getting so many key players back as they embark on the second half of the season has the 4-4 Niners believing big things are possible down the stretch.

"This is the grind of the season now, the stretch we're about to go on, and we need all our weapons," linebacker Fred Warner said. "And it's great to see some familiar faces out there. ... We're gonna need them."

Samuel, Juszczyk and Jennings each missed just one game, but having that trio allows the offense its first opportunity to see how things look when Samuel and recently acquired running back Christian McCaffrey work in tandem with a skill position group that also boasts tight end George Kittle, Mitchell and wide receiver Brandon Aiyuk.

"It's just so crazy how much firepower we have in this offense now with adding [McCaffrey] to the team along with all the other guys that we've got," Samuel said. "It's gonna get crazy. It's gonna be hard to cover everybody out there, and it should be real fun."

The defense will also benefit from some post-bye reinforcements. The return of Al-Shaair and Greenlaw means the 49ers' primary linebacker trio will be together for the first time since Week 3.

Al-Shaair's return comes a bit earlier than expected, but he said Monday that he was feeling good and ahead of schedule after rehabbing with Mitchell.

"Realistically, it was like six to eight [weeks], but initially I thought it would be eight," Al-Shaair said. "You're usually conservative up front. And then you kind of just see where each person goes, and I was doing a lot better than they thought. So I was able to get back out there."

The news wasn't all good for the Niners, who have lost cornerbacks Verrett and Emmanuel Moseley (torn left ACL) for the season and will be without defensive tackle Arik Armstead (foot, ankle), who was ruled out on Friday. Defensive end Samson Ebukam (quadriceps) is listed as doubtful.

Even without those players, the Niners know the value in giving others a chance to be on the field. Shanahan said it can be beneficial because the Niners are still in the playoff mix with other players having the chance to play meaningful snaps.

"It helps a lot," Shanahan said. "When you lose guys, it puts you in a bind. The only benefit to losing guys is it gives other people the opportunity to develop because they have to go through stuff. And sometimes the only time you get better is going out there and getting your butt kicked and realizing what you've got to do in this league because you can't always simulate that. ... If you can kind of still not set your team back, it can make your team a little bit stronger."