‘Chargers star wide receiver Keenan Allen, who leads the NFL in receptions, is dealing with a heel injury. He missed the game against Las Vegas on Thursday, and did not practice Tuesday. Chargers interim head coach Giff Smith called Allen’s injury “tricky.” Los Angeles placed starting center Will Clapp on injured reserve Wednesday due to a knee injury suffered on Thursday. Cameron Tom, who has one career start, could replace Clapp.’