Head coach Antonio Pierce said Koonce is out for Sunday's game against the Chargers with knee soreness, Vic Tafur of The Athletic reports.
Pierce did not expand on Koonce's injury or how it occured, but the defensive end will at least be out against Los Angeles. Janarius Robinson will likely assume the starting defensive end spot for Sunday, accompanying the front of Maxx Crosby, John Jenkins and Christian Wilkins. Koonce's next chance to see the field will be next Sunday against the Ravens.