Kellen Clemens is an 11-year veteran who has a firm grasp of the Chargers offense and, as evidenced by his uneven preseason play and the fact he’s thrown 10 regular-season passes in three years with the team, a limited ceiling.
Second-year pro Cardale Jones, acquired from Buffalo in August, has considerable physical gifts — size, strong arm, nimble feet — but might lack the touch and command of the offense to step in and be effective.
The Chargers open the 2017 season at Denver on Monday night with one of the league’s best quarterbacks in Philip Rivers, the 35-year-old gunslinger who ranks 12th on football’s all-time passing list with 45,833 yards in 13 years and has made 185 consecutive starts dating back to 2006.