What does it take to beat the 13-3 Denver Broncos on their home turf? Just ask the San Diego Chargers.
On a Thursday night in Week 15, the Chargers headed to Mile High and took charge of their matchup with the eventual AFC West champs. They did so by (among other things) establishing a run game early, limiting Peyton Manning's ability to stretch the field and exploiting some gaps in Denver's pass defense.
There was nothing overly exotic in the gameplan -- the Chargers took what Denver gave them in most cases, while constricting how the Broncos could counter.
For any team -- be it the Chargers or a future foe -- to knock off the Broncos this postseason, it will require a similar attack. So here's a closer look at how San Diego went about its business earlier this season:
Let's start with Manning, as most discussions do with regard to the Broncos. He fired four touchdown passes in a Week 10 win at San Diego, rather surgically slicing his way through the Chargers defense. The rematch was a different story: Manning was held to 289 yards, marking one of just four times he failed to reach the 300-yard plateau this season. (Denver finished 2-1 in the others, with wins over Oakland and Jacksonville and a loss to New England.)
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But more important than the yardage total was how Manning reached it. He averaged just 7.1 yards per attempt, a full yard behind his season total of 8.3. And his longest completion of the day was a 22-yarder to Julius Thomas. Considering that Manning broke the NFL's single-season passing yardage record this season, that constitutes a near-complete shutdown. Manning also hit on 48 passes thrown 20 yards or more downfield, per Pro Football Focus.
There were two key elements in how San Diego kept Manning from hitting downfield: safety positioning and disguised fronts.
San Diego played its safeties well off the line, often in two-deep schemes. Utilizing that setup in combination with relatively loose man-to-man looks at the line dropped the Chargers into a rather soft shell -- one that corralled Denver's passing attack into about a 15-yard window. The San Diego D also opted to prevent those deep passes at the risk of Manning dumping the ball off in the flat or underneath.
Example A, with both Chargers safeties providing help over the top and RB Montee Ball slipping out of the backfield uncovered.
Manning dumped a pass off on this play to Ball for about a five-yard gain -- nothing to sneeze at, necessarily, but far preferable for San Diego than allowing a bomb to Eric Decker or Demaryius Thomas. It was almost a prevent-defense approach, as San Diego forced the Broncos to play small ball rather than swing for the fences.
Though the Colts allowed 33 points in their win over Denver this season, they often utilized a similar approach:
That's a trips formation for Denver releasing into four Colts defenders, with a fifth (the second safety) coming across the field to help. In this example, Indianapolis managed to flip the numbers advantage in its favor, from a coverage perspective.
San Diego pulled off a similar trick by flashing blitzes, then dropping multiple defenders into varied coverages. Case in point: This play pictured below, where the Chargers had six defenders in the box at the line of scrimmage. Only three came after Manning, with a fourth pass-rusher coming off the edge in a cornerback blitz.
San Diego also slid one of its safeties up into the middle of the field, leaving a Cover-1 deep ... but confusing Denver closer to the line.
Again, the numbers swung in San Diego's favor. Even though the Chargers rushed just four players, the Broncos were forced to keep Montee Ball in as an extra blocker. That left Denver with four receivers out running routes against seven Chargers.
Had the blocking not been there, San Diego would have succeeded in accomplishing yet another key against Denver: pushing Manning from his spot in the pocket. The result on this play, though, was that Manning had almost nowhere to go, short of checking it down to his right with Eric Decker.
Instead, Manning tried to force one into coverage on the other side of the field -- a decision that resulted in an interception.
Again, there's nothing groundbreaking here, as the San Diego gameplan wasn't all that different from what other teams have tried against Denver. The Chargers. however, executed in all phases.
That includes on offense, where the strategy was the same: create favorable matchups in personnel. Teams that run the option -- either a traditional one or the read-option -- operate under the same principles, in that the No. 1 goal is to outman the opposing defense. When Denver provided San Diego's offense with those same opportunities, it took them, particularly in the run game.
Here, the Broncos had four defenders on the line, but just two true defensive lineman. The two players out wide were linebackers Von Miller and Shaun Phillips. So, San Diego ran between the tackles.
Ryan Mathews ran away from Miller, thus allowing TE Ladarius Green to neutralize Denver's top defender (who will not play Sunday due to a season-ending injury). To Mathews' left, the Chargers' linemen managed to get a hat on the defenders directly in front of them, leaving Mathews with a cutback lane up the middle and a wide option blocked only by safety Mike Adams.
Mathews probably missed the real hole there -- had he found the gap up the middle, he may have scored a touchdown. He picked up a nice gain outside, however, as Adams found himself caught in the muck between the hash marks.
One more case of creating the mismatch in the run game, from later in that Week 15 contest.
This time, the Chargers negated Phillips (90, right) by running away from him, then used a pulling lineman and TE Antonio Gates to fill holes at the A- and B-gaps, respectively. Assuming the Chargers do not miss their blocks, who is supposed to tackle Mathews?
The principle concepts in San Diego's Week 15 passing attack were the same, particularly in relation to WR Keenan Allen. Denver flashed a lot of man-to-man coverage; San Diego countered by doing whatever it could to get the football into its playmakers hands early, thus allowing them to thrive on the limited attention.
One of Allen's touchdowns in the game came against that man-coverage. He lined up to Philip Rivers' left, with two receivers and Gates to the right. RB Danny Woodhead set up shop next to Rivers in the backfield.
Notice below how Woodhead comes out of the backfield to Rivers' left and is immediately met by a defender. That's a contrast to the photo earlier, which showed San Diego allowing Manning to use Ball as a check-down option. Committing to Woodhead left one less defender in the middle of the field, which in turn helped clear space for Allen to catch and run.
Indianapolis' Stanley Havili scored a TD versus Denver in a comparable manner -- with his fellow receivers on the play running Denver's man-coverage out of the way, freeing a huge chunk of the field.
Will the Broncos utilize more zone looks on defense this week? Softer coverages in the man-to-man looks? They might opt for a little of both, considering how Rivers picked apart their pass defense in Week 15. Denver really failed in its attempts to dictate what San Diego could do on offense, as it failed to adequately cover the Chargers' receivers and did not have the strength up front to take away the run game.
One more play, and another glimpse of a problematic situation for the Broncos. This was a pass play out wide, but the Chargers again had a shot at controlling the numbers in the box had Rivers checked to a run -- five linemen plus Gates against two DTs, two rush linebackers and a middle linebacker.
Out wide, the Broncos were not in much better shape. A wheel route for WR Vincent Brown gave him a step on his man-coverage to the boundary, leaving Rivers enough room to fire him a pass before safety help could arrive.
This was the fundamental problem for Denver in Week 15: San Diego consistently won head-to-head matchups all over the field, be it at the line or in the secondary. Couple that with the Chargers' simple and conservative scheme -- one that forced the Broncos out of their comfort zone, at least on offense -- and you have a San Diego road victory.
Denver had an edge in talent on paper, just as it will again this week. The Chargers overcame those deficits by dictating situations on both sides of the football.
If they're going to upset the Broncos for a second time, they'll have to do all these things again.
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