Two teams in the thick of the playoff chase will battle it out in Jacksonville as the Jaguars host the San Diego Chargers.  The Jags are coming off a 28-13 triumph at Tennessee and now trail the first-place Colts by just one game in the AFC South.  Quinn Gray passed for only 101 yards and a touchdown for Jacksonville, which returns home after playing its last three games on the road.  The 5-and-4 Chargers lead the AFC West after a Sunday night win over Indianapolis in which they intercepted Peyton Manning six times.  San Diego nearly blew a 23-0 lead, but escaped with the victory thanks to a late missed field goal by Adam Vinatieri.  QB Philip Rivers looks to bounce back after throwing for just 104 yards with two picks.