Jeff Darlington and Jack Del Rio see the Chargers' loss of Derwin James as huge and discuss the possibility of James missing the entire season. (1:14)

Los Angeles Chargers All-Pro safety Derwin James is expected to be sidelined three to four months after surgery on his right foot, sources told ESPN's Adam Schefter.

James will undergo the surgery on the stress fracture of his right foot next week with Dr. Robert Anderson, a source confirmed.

NFL Network first reported that James would undergo surgery.

That timetable means James could be back for a playoff push or the postseason.

James suffered a stress fracture of the fifth metatarsal of his right foot at practice on Thursday. He was seen with a walking boot on his right foot at his team's second joint practice with the New Orleans Saints on Friday. Dr. Anderson is the same doctor who treated James' teammate Joey Bosa last year when he suffered a bruised left foot that forced the Ohio State product to miss the first nine games of the regular season.

The Chargers finished 7-2 without Bosa in 2018.

"There's nothing that you can say," Bosa said, when asked about James' injury on Thursday. "Everyone is walking up to him and asking, 'How are you doing?' There's really nothing you can say to make a guy feel better in that situation. You just have to let him know that you're there for him, offer him any help if he needs it. I really feel for him."

With this timeline, the Chargers likely will place James on injured reserve, which means James would have to miss at least the first eight games of the regular season before the team could designate him to return to the field once healthy.

"With his production and his intangibles, we're going to miss him a lot," Chargers head coach Anthony Lynn said. "But we're a team. I think that we have a good team. We have guys that will step up. We will be fine. We lost Joey last year. We were fine and then we got him back. We'll be OK."

James suffered the injury during Thursday's joint practice against the Saints when someone stepped on his foot, although he did not miss any time and appeared fine, corralling an interception at the end of the session.

Fellow Pro Bowler Adrian Phillips worked with the starters at strong safety with James unavailable.

James had not missed a training camp practice and played 11 snaps in the Chargers' opening preseason game last week against the Arizona Cardinals.

The Florida State product also played in all 16 games last season. He led the Chargers in tackles (105) in 2018, also posting 3.5 sacks, three interceptions and 15 pass breakups, earning All-Pro and Pro Bowl honors as a rookie.