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When the Chargers face the crosstown rival Rams Saturday night, they'll do so without star quarterback Justin Herbert. Los Angeles coach Brandon Staley revealed Thursday that Herbert, running back Austin Ekeler, receiver Keenan Allen and strong safety Derwin James will not play during the 2021 preseason. The first time these players will take the field will be when the Chargers travel to Washington for their regular-season opener on Sept. 12. 

With Herbert out, expect preseason reps to be split between Chase Daniel, Easton Stick and rookie K.J. Costello. A 12-year veteran, Daniel -- who signed with the Chargers this offseason after spending the last two seasons with the Bears -- will start Saturday's game against the Rams. Stick was the only other Chargers quarterback other than Herbert who threw a pass during the 2020 regular season. An undrafted rookie, Costello threw 55 touchdowns against 29 interceptions during a college career that included three seasons at Stanford and an additional year as Mississippi State's starter. 

Herbert, the reigning NFL Offensive Rookie of the Year, completed nearly 67% of his passes for 4,336 yards and 31 touchdowns last season. His favorite target was Allen, who was selected to his fourth straight Pro Bowl after catching 100 passes for 992 yards and eight touchdowns. Ekeler, who missed six games last season due to injury, amassed 993 all-purpose yards and three touchdowns during this fourth season with the Chargers. 

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An All-Pro performer in 2018, injuries have limited James to just five games over the past two seasons. He missed the entire 2020 season after undergoing surgery to repair a torn meniscus last September. 

"Our practices are going to be a lot more like games than these preseason games," Staley said when explaining his reasoning behind keeping James out of the preseason. "The environments that we create on our practice fields is where the real action is in the preseason for guys like him.

"I've been so excited to see him compete against all of the special players that we have. We feel like that's the right environment for him to get ready for the season."