COSTA MESA, Calif. -- The Los Angeles Chargers have lost yet another starter to a season-ending injury.
Defensive tackle Austin Johnson will miss the remainder of the season after suffering an MCL sprain and fracture to his left knee in Sunday's 20-17 victory over the Atlanta Falcons, coach Brandon Staley said Monday.
"I'm disappointed because Austin has been fantastic since he's gotten here," Staley said. "We love coaching him, but this is part of the NFL."
Johnson, a seventh-year pro, will join edge rusher Joey Bosa, cornerback J.C. Jackson and left tackle Rashawn Slater on injured reserve.
The Chargers are optimistic that Bosa will return at some point this season. Jackson and Slater, however, will not.
Also, in the victory over the Falcons, right tackle Trey Pipkins III aggravated a left MCL issue and is day-to-day, Staley said.
Despite dealing with a plethora of injuries, the Bolts are 5-3, in second place in the AFC West behind the Kansas City Chiefs, and on track to earn their first playoff berth in four seasons.
Wide receivers Keenan Allen and Mike Williams, kicker Dustin Hopkins, defensive lineman Jerry Tillery and edge rusher Chris Rumph II are also dealing with injuries that have caused them to miss time.
Staley said that Allen, Hopkins, Tillery and Rumph are day-to-day in their recoveries, but that Williams was week-to-week.
After signing a two-year, $14 million contract in free agency, Johnson started all eight games this season. He finishes with 22 tackles, a sack and a pass deflection.
Staley said it would be a work in progress as to who replaces Johnson.
"We're going to work through that over the next 36 hours and get out there on the practice field," Staley said. "You'll probably have a better idea of it then."
Candidates on the active roster include eight-year pro Christian Covington and rookie Otito Ogbonnia.
The Chargers will play the San Francisco 49ers (4-4) in a Week 10 matchup at Levi's Stadium on "Sunday Night Football."