People snickered when Mike McCoy said last May that Philip Rivers could connect on 70% of his passes in the Chargers' new spread offense. Turns out the first-year coach was prophetic—almost. Rivers had an NFL-high 69.5% completion rate and 32 TDs (fourth in the NFL), earning his fifth Pro Bowl invitation and quieting speculation about his future in San Diego.

Few imagined that the Chargers, who on Dec. 1 were 5--7 and still had the Broncos and the Chiefs remaining on their schedule, would be among the NFL's final eight. In fact, few had believed in the team when it opened camp with mostly the same roster that had stayed home the last three postseasons. The offense seemed particularly uninspired. Rivers had not been impressive since 2010, when he threw for 4,710 yards and 30 TDs; the running game had gained only 91.3 yards per outing in '12 (27th in the NFL); and the O-line, revamped in three of five spots this season, was short on athleticism and experience. Doubts intensified in September when No. 1 wideout Malcom Floyd (sprained neck) joined No. 2 wideout Danario Alexander (torn right ACL) on IR. Replacing the two 6'5" deep threats would be 5'11" Vincent Brown (four career starts) and either 5'10" return specialist Eddie Royal or 6'2" Keenan Allen, a third-round pick out of Cal.

But the beauty of a spread system like McCoy's is that it can dilute weaknesses. Athleticism and experience are less important along the line when the QB is getting rid of the ball on a three-step drop, which is the norm, as wider formations make passing lanes and defensive schemes easier to identify before the snap. Run blocking is less about moving an opponent than about neutralizing him just enough to maintain preexisting spacing. The spread can't succeed with a terrible line, but it can with one whose best assets are undersized center Nick Hardwick and monstrous (if lead-footed) rookie tackle D.J. Fluker.

Pre-snap looks often determine where quick throws go in the spread, so for receivers, the keys are fundamentals and timing, not raw talent. The Chargers also don't lean as much on wideouts as they do on tight ends Antonio Gates and Ladarius Green and running back Danny Woodhead, who can all split out and win mismatches against safeties and linebackers.

But a spread—especially one that often goes no-huddle—cannot prosper without a quarterback who is adroit at the line of scrimmage. This season Rivers has been terrific at repositioning receivers and adjusting protection. And he has always been brave and valiant in the pocket. While Gates remains his primary weapon, more of Rivers's throws as plays break down are going to Allen, who has a knack for making catches against tight coverage.

Productive as the spread has been, it's the emergence of a power-zone rushing attack that has propelled the Chargers to five straight victories, including Sunday's 27--10 win over Cincy, in which San Diego ran for a season-high 190 yards. Overall, Ryan Mathews has finally looked like the sturdy slasher San Diego's previous regime traded up to draft with the 12th pick in 2010, averaging 24.0 carries and 105.0 yards over the last five games. If this offense can rush well enough, foes will stay in reactive mode, creating even more advantages for a well-orchestrated spread. Factor in a well-coached, peaking defense, and these Bolts might just shock the world.


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