Jaguars: Sen'Derrick Marks sets tone for defense in San Diego.

There was precious little reason to applaud about the Jacksonville Jaguars defensive efforts through the first three weeks of the season. An aggressive performance during the first half in Philadelphia gave way to 10 quarters of ineptitude, as missed tackles, busted assignments and soft play became the norm.

That changed against the San Diego Chargers, when Sen'Derrick Marks swam past guard Chad Rinehart to sack Philip Rivers on the Chargers second offensive snap of the game. From that point on, the Jaguars defensive front played with an impressive intensity, forcing Rivers to play at an elite level to get ahead.

Both Marks (+4.3) and Roy Miller (+3.8) each had their best games of the season, dominating the middle of the line of scrimmage. One sack, one QB hit and three hurries gave Marks a 15.4 Pass Rushing Productivity grade, which led defensive tackles with 20 or more pass rush snaps in Week 4.  Miller tallied two defensive stops in 9 snaps against the run.  Their efforts may have went without reward against the Chargers, but if that intensity can be sustained, brighter days should be ahead for the winless Jaguars.