Source: Derwin James out as ailing Chargers face Dolphins

LOS ANGELES -- The Chargers will be without several key players on defense when they face the Dolphins on "Sunday Night Football."

Safety Derwin James Jr., defensive lineman Sebastian Joseph-Day and cornerback Bryce Callahan will be out because of injuries, a source told ESPN.

Right tackle Trey Pipkins III, listed as doubtful, also is expected to be out as he continues to nurse a knee injury that sidelined him last Sunday.

The Chargers are 6-6 and still looking for their first victory against a team with a winning record (they're 0-4) as they prepare for the Dolphins (8-4).

James, whose responsibilities range from playing safety to lining up at cornerback, linebacker and even on the edge, leads the Chargers with 106 tackles and has four sacks, four pass deflections, two forced fumbles and an interception this season. The fifth-year pro has been dealing with a quadriceps injury that he suffered in a Week 12 victory over the Arizona Cardinals. James played through the injury last Sunday in a 27-20 loss to the Las Vegas Raiders.

In his absence, safeties Alohi Gilman and rookie JT Woods will be expected to step in.

The loss of Joseph-Day, who is dealing with a right knee injury, also is significant for a defensive front that has already lost several players to injuries. Edge rusherJoey Bosaand linemen Austin Johnson, Otito Ogbonnia and Christian Covington are on injured reserve.

Callahan, who is dealing with a groin injury, leads the team with three interceptions and is expected to be replaced by rookie Ja'Sir Taylor.

The likely absence of Pipkins at right tackle means that quarterback Justin Herbert will be playing behind a pair of backup tackles for a third time this season. Pro Bowl left tackle Rashawn Slater was placed on injured reserve after Week 3. Foster Sarell, an undrafted free agent in 2021, would be expected to start in place of Pipkins for a third time this season.

With five games remaining, the Chargers have a 61.2% chance to make the playoffs, according to ESPN's Football Power Index.