The Jacksonville Jaguars’ Super Bowl dreams are turning into a nightmare. And the obvious culprit is quarterback Blake Bortles, who was benched early in the second half of Sunday’s 20-7 loss to the Houston Texans — the team’s third-straight defeat.

A civil war appeared to erupt after the game in the locker room, which beat writer Daniel Popper of The Athletic described as having “surpassed 212 degrees Fahrenheit.”

“The Jaguars are sinking helplessly into the burning cauldron with no lifeline in sight,” Popper wrote on Twitter.

The defensive players were yelling the loudest, so the narrative is that the finger-pointing is at Bortles and the club’s offense. But those fingers may be pointing the wrong way: The real reason for the team’s struggles is that its super-human defense is not merely regressing as expected in forcing turnovers and converting them into touchdowns — it’s collapsing.

2018 Blake Bortles compared with his career average prior to this season 2018 Career Passer rating 80.3 80.8 Yards per pass play 6.41 5.98 QBR 48.2 45.5 Sources: Pro-Football-Reference.com, ESPN Stats & Information

There’s no denying that Bortles and the offense are a problem. But this was perfectly predictable. This year, Bortles is playing exactly like you would have expected. His QBR and passer rating are similar to his career rates, and his yards per dropbacks metric is actually significantly better.

Bortles has led his team to only 34 points in four losses, though all of those came without bell-cow running back and 2017 fourth-overall pick Leonard Fournette in action. While the Jaguars have averaged 4.3 yards per rush this year, the same rate as in 2017, it could reasonably be argued that defenses no longer need to focus as much on stopping the run, making the sledding more difficult for Bortles and the passing game.

But more importantly, last season the Jaguars could count on getting some offense from their defense. They had a league-high seven return touchdowns on picks and fumbles in 2017. But this year, they have had only one — and none in the games they lost. And their defense is not even setting up their offense with good field position via the turnover, as they had just two takeaways in the four defeats after finishing second in the league last year by averaging more than two per game.

Jacksonville’s defense regressed even more than expected NFL teams from 2010 to 2016 that had at least 30 takeaways and five defensive touchdowns with how they fared the following year, along with the 2017-2018 Jacksonville Jaguars year FOllowing year Defense Year Take-aways League Rank Def. TDs Take-aways League Rank Def. TDs Jaguars 2017 33 2nd 7 5 29th (tied) 1 Chiefs 2016 33 1st 5 26 7th (tied) 3 Cardinals 2015 33 2nd 6 28 4th (tied) 3 Texans 2014 34 2nd 5 25 12th (tied) 3 Chiefs 2013 36 2nd 7 14 30th (tied) 1 Bengals 2013 31 3rd (tied) 5 26 10th (tied) 3 49ers 2013 30 6th (tied) 5 29 4th (tied) 3 Cardinals 2013 30 6th (tied) 5 25 14th (tied) 4 Bears 2012 44 1st 9 28 13th (tied) 6 Patriots 2012 41 2nd 5 29 10th (tied) 3 Packers 2011 38 1st (tied) 5 23 18th (tied) 2 Lions 2011 34 3rd (tied) 7 17 27th 0 Bears 2011 31 5th (tied) 5 44 1st 9 Bills 2011 30 9th 6 21 23th (tied) 1 Patriots 2010 38 2nd 5 34 3rd 3 Cardinals 2010 30 8th 10 19 26th 0 Source: Pro-Football-Reference.com

Make no mistake, the Jaguars defense overall is still very good — second in yards allowed and second in yards allowed per pass play. It’s just not supplementing an offense that needs supplementing. So now the Jaguars attack isn’t Bortles-plus — it’s just Bortles. And completely unsurprisingly, “just Bortles” is not a recipe for NFL success.

NFL teams this decade that had at least 30 turnovers and at least five defensive touchdowns generally badly regressed — from an average league rank of 3.5 in turnovers to 13.5. But the Jaguars thus far have gone from second to a tie for 29th. So now a team that appeared poised to return to the postseason after reaching the AFC Championship is on life support.

Head coach Doug Marrone seemed to concede after Sunday’s game that Bortles wasn’t really to blame for the team’s woes, but he had to do something.

“I just literally did it to try to get a damn spark from this football team, to put everyone on notice that they have to focus, and they have to go out there and play better,” he told reporters. “That’s not fair to the quarterback, but that’s the way this business is. … The one thing you do with that position, doesn’t matter the name, doesn’t matter who it is: When you make a move to get a spark, everyone goes on notice. Everyone.”

But the spark Marrone was trying to get isn’t really the spark that the Jaguars need. It’s some turnovers.

There’s a chicken and egg issue here though. Turnovers are easier to come by when you have the lead. In 2017, the Jaguars forced 41 sacks and 13 picks in 372 pass plays while they were leading — when the opposing offense was more reckless and pass-happy.

Those 372 plays were 63 percent of all opponent dropbacks last year and led to 62 percent of the Jags’ picks and 75 percent of their sacks. This year, opponents are throwing only 44 percent of their passes while trailing — and those plays accounted for just 47 percent of their sacks and 33 percent of their picks.

So the way for the Jaguars to function better as a team is for someone on either side of the ball to make a play early and give Jacksonville a lead. They’ll get a chance Sunday in London against another team that’s learning that success in the NFL is far from stable, the defending champion Philadelphia Eagles, who are also just 3-4. But if the Jags can’t turn it around, the temperature in their locker room might never go down.

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