The Steelers’ epic comeback Sunday began with a change in philosophy from the Colts

The Pittsburgh Steelers stormed back from seventeen points down late in the 3rd quarter to knock off the Indianapolis Colts on Sunday, 28-24, clinching the AFC North and a home playoff berth in the process.

It was an improbable victory considering how the first forty-odd minutes of play transpired, with Indy dominating on both sides of the football. Their defense had been particularly effective, holding the Steelers to 171 total yards on 37 snaps for an average of 4.6 yards per play. Pittsburgh’s only points had come courtesy of a three-yard drive set up by a turnover from their defense.

Then, trailing 24-7 with 3:22 to play in the 3rd quarter, the Steelers took possession on a short field. From the Colts’ 39 yard line, Ben Roethlisberger hit Diontae Johnson on a go route for a touchdown. Johnson’s sprawling grab ignited a unit that had been dreadful for the better part of a month. The Steelers scored on 74 and 84 yard drives their next two possessions to surge ahead, and the defense held up in the final minutes to secure the win.

What sparked the offensive explosion? How did a group that had looked slow, soft and disoriented for five straight weeks suddenly morph back into its early-season form? In part, the execution simply improved. The line blocked, the quarterback was decisive and the receivers caught the football. It had been a while since the offense was able to do all those things in unison for an extended period of play.

As their execution improved, so did their confidence. Ben Roethlisberger returned to the no-huddle tempo and looked as comfortable doing it as he had in the Week 8 comeback win at Baltimore. That game, incidentally, also finished 28-24. Roethlisberger broke his habit of rushing the ball out of his hand by standing in the pocket to extend plays, using his signature pump-fake to manipulate defenders, pushing the football down the field and, most importantly, being (mostly) accurate when he did. The receivers fed off of Roethlisberger’s performance, making tough, contested receptions, running hard after the catch and securing the football. The line, for its part, left Roethlisberger largely unscathed.

Indianapolis, however, offered the Steelers a substantial assist. The Colts backed off of the aggressive scheme they’d deployed for the first two-and-a-half quarters and dropped back into soft coverage. The Steelers took advantage, ringing up huge numbers once Indy adjusted.

When Pittsburgh got the ball on the one-play possession that resulted in Johnson’s touchdown, kick-starting their comeback, the Colts had been extremely effective when playing single-high safety coverage. They crowded the Steelers’ receivers at the line of scrimmage, pressured Roethlisberger and allowed safety Khari Willis to drop down and disrupt routes in the underneath zones. Willis also made a host of tackles against the run, where Pittsburgh could not account for him with a blocker. The Colts had only played a small number of snaps in cover-two or cover-four with Willis out of the box. And for good reason. Consider how the Steelers had fared against both looks:

Steelers’ Offensive Snaps Prior to DJ touchdown:

Vs. 1-high looks (75.6 % of snaps) 28 plays, 104 yards, 3.7 ypp

Vs. Cover 2/4/6 looks (24.4% of snaps): 9 plays, 67 yards, 7.4 ypp

Here was a typical look from Indy in those first three quarters, with defenders crowding the ball and showing a pre-snap pressure look:

Sometimes the Colts brought their backers inside. Sometimes they pulled the backers off and came from the edge. Here’s the aforementioned Willis coming clean on a safety blitz to drop Roethlisberger:

Often, Pittsburgh’s receivers struggled to separate from the tight coverage. It made sense, then, for Indy to stay aggressive in the second half, even when they extended their lead to 24-7.

They did not. The Colts got conservative, falling back into safer coverage looks. In theory, this made sense. It’s what every defensive coordinator trying to protect a second half lead does. Back in the day, this was called “prevent” defense. The joke was that the only thing it prevented was the team running it from winning. Defenses have evolved, but the basic idea remains the same: protect against the deep ball, don’t give up chunk plays and make the offense drive the field to score.

Why did Indy switch? On Pittsburgh’s opening drive of the second half, Roethlisberger hit Chase Claypool on a skinny post against single coverage for 34 yards on a drive that saw the Steelers turn the ball over on downs at the Indianapolis two yard-line:

It was a vintage Roethlisberger throw — ripped on a line thirty yards down the field against tight coverage. It’s possible that completion got into the head of Indianapolis defensive coordinator Matt Eberflus. Roethlisberger has gotten into the heads of a lot of DCs throughout his career. Just none lately. That one, however, may have convinced Eberflus to pull back.

Also, Willis, the versatile safety, left the game late in the third quarter with a head injury. Eberflus may not have felt comfortable running his more aggressive schemes without Willis on the field.

Whatever the case, the Steelers fared remarkably well once Indy backed off:

Steelers’ Offensive Snaps, DJ Touchdown to End of Game:

vs. One-high looks (33.3% of snaps): 8 plays, 26 yards, 3.3 ypp

vs. Cover 2/4/6 looks (67.7% of snaps): 16 plays, 158 yards, 9.9 ypp

Indy went with two-high looks on two-thirds of its remaining defensive snaps. The Steelers gashed them when they did, averaging nearly ten yards per play. Roethlisberger was 12-13 passing for 140 yards versus cover two, four and six. Indy stopped blitzing, stopped playing cover-1 and stopped dropping a safety down. The benefits for Pittsburgh were remarkable.

It started with the touchdown to DJ. The Colts were in a cover-6 look, playing cover-2 to the field and cover-4 to the boundary:

Roethlisberger had Johnson matched up one-on-one to his right against corner Rock Ya-Sin. Safety Tavon Wilson would help on the slot receiver if he went vertical. If he went in or out, Wilson would help on Johnson. Johnson ran a straight take-off and topped Ya-Sin, whose zone turn caused him to lose his relationship with Johnson ever-so-slightly. Wilson, meanwhile, seemed to sit on a post move from Johnson and did not get enough depth to help on the vertical. Roethlisberger threw a perfectly-placed ball and Johnson laid out beautifully to haul it in for the touchdown:

On Pittsburgh’s next drive, Indy played two-high on every snap but one. Roethlisberger completed 4-5 passes for 29 yards on the drive and drew a pass interference call on corner T.J. Carrie, who was beat on on a seam route by Johnson on the only snap Indy played in drop coverage:

The Steelers were now doing something they’d failed to do for weeks: pushing the ball downfield. The four-man pass-rushes the Colts were sending at Roethlisberger were being handled easily by the offensive line, giving Roethlisberger plenty of time to set his feet and throw. With Roethlisberger comfortable in the pocket, the downfield passing game opened up.

On the drive that put the Steelers ahead, Indy clung to their two-high strategy. Roethlisberger went 6-8 for 69 yards, including the dagger to Juju Smith-Schuster off of a vintage Big Ben pump-fake that froze the linebacker and safety (circled below) and gave him enough space to fit the ball up the seam:

The safety, in particular, stopped his feet in anticipation of a quicker throw, likely the dig route coming from Johnson on the opposite side of the formation. The fact that Roethlisberger pumped the dig then came back to the divide from Smith-Schuster suggests he had a great idea how the safety to the boundary would react and knew exactly how to manipulate him:

In the wake of this stunning defeat, Indianapolis is now on the outside of the playoff picture looking in as we head to the final week of the season. They will need one of the three teams ahead of them for the wild card playoff spots in the AFC to stumble. If Indy does not get in, I can’t help but think they’ll mourn the decision to switch their defensive philosophy in the second half against Roethlisberger and the Steelers. Despite a month’s worth of evidence that suggested the road-map to stifling the Pittsburgh offense was pressure and disruption, Indy instead decided to back off, give the receivers room to run and Roethlisberger time to throw. The Steelers, to their credit, took advantage.

One man’s misfortune is another man’s opportunity. The Steelers have a big one now, with the division locked up, a chance to rest their key players in next week’s finale against Cleveland and, most importantly, a huge dose of confidence back in their offense. If Pittsburgh manages to make some noise in this season’s playoffs, they’ll have the final eighteen minutes against the Colts, and the fortunate adjustment Indy made on defense, to thank for it.