Head coach Jim Harbaugh said Monday that Kolar will go on injured reserve due to a forearm injury he sustained during Sunday's 26-14 loss to the Raiders, Kris Rhim of ESPN.com reports.
Kolar was spotted with his left arm in a sling following Sunday's loss, and the injury is severe enough for him to warrant a stint on IR. As a result, Kolar will be forced to miss at least the next four games, making him ineligible to play until Week 8 against the Rams. David Njoku (knee) is also set to go on IR, leaving Oronde Gadsden as the lone healthy tight end on the Chargers' 53-man roster for the time being.