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It always felt like there was only one team in the AFC not named the Pittsburgh Steelers that could knock off the New England Patriots.

That team is the Jacksonville Jaguars, and merely mentioning them as a threat to the Patriots still feels like something only Jason Mendoza could say with sincere enthusiasm. Remember, the old Jaguars hadn't made the playoffs in nine seasons before winning the AFC South in 2017. They fired through three head coaches during that time and didn't have a record above .500.

But the new Jaguars posted a double-digit win total for only the sixth time in franchise history. They've fumigated the wretched stink of that old, embarrassing franchise with an impressive one-year turnaround after adding core pieces during the draft and free agency (most notably, defensive backs A.J. Bouye and Barry Church, and defensive end Calais Campbell).

Their offseason maneuvering resulted in a team that has the two core elements needed to beat the Patriots: a pass rush and a rushing offense, with the ability to hand out punishment in equal doses.

The latter is where the Jaguars' hopes of another stunning upset lie Sunday. The same was true during the divisional round when running back Leonard Fournette finished with 109 rushing yards in a 45-42 win over the Steelers, the other AFC heavyweight.

Even more impressively, Fournette scored three touchdowns on the ground. As ESPN Stats & Info noted, he made history when two of them came in the first quarter alone.

No amount of powering through and weaving around defenders from Fournette will change the identity of the 2017 Jaguars.

They're a team rooted in defensive swarming and smothering, which begins with a pass rush led by defensive end Calais Campbell and his 14.5 sacks. The Jaguars finished the year ranked second in sacks (55), and creating intense pressure has been a way to beat Patriots quarterback Tom Brady in the past.

During the conference championship game for the 2015 season, the Denver Broncos hit Brady 20 times, which held him to a completion percentage of only 48.2 in a loss.

More recently, the Miami Dolphins earned a surprising regular-season win over the Patriots late in 2017 by pressuring Brady on 35.6 percent of his dropbacks, per Evan Lazar of Pats Pulpit. In that game, Brady averaged only 5.4 yards per attempt, significantly lower than his overall season average of 7.9 yards.

But winning with defense, and defense alone, will be difficult against the Patriots because of their emerging offensive weapon who can neutralize a pass rush. Running back Dion Lewis, the multithreat slasher who thrives in space, can cut up defenses when targeted on screens and short, quick throws. Lewis has piled up 206 receiving yards out of the backfield over his last five games, including 79 yards during the divisional round.

The Jaguars will need an added layer of defense, and that could come from the offense sustaining drives and keeping Brady on the sideline in his giant coat.

They'll have to lean on a rushing offense that begins with Fournette.

Fournette is the soul of the Jaguars' backfield. He finished his rookie season with 1,342 yards from scrimmage. He missed three games due to a recurring ankle injury and suspension and was limited in others. But the 2017 fourth overall pick has still recorded eight games with 100-plus total yards, including the playoffs.

He powered the Jaguars' top-ranked rushing offense and will now look to exploit a Patriots defense that has been feeble at times when defending the run. New England gave up an average of 114.8 rushing yards per game during the regular season (20th).

Over two games against the Steelers and their 10th-ranked run defense, Fournette scored five touchdowns and ran for 290 yards, averaging 5.5 yards per carry. At 6'0' and 228 pounds, and with a 40-yard dash time of 4.51, Fournette is a tackle-busting bruiser.

He's had that label ever since breaking a nation-leading 85 tackles in 2015 at LSU. Now Fournette has carried over his punishing reputation to the NFL. Before leaving the game briefly due to an ankle injury midway through the second quarter, he rumbled for 47 yards after contact against the Steelers, according to Pro Football Focus.

That led to the latest in what's now a long stretch of dominance for the Jaguars backfield:

Jaguars rushing over the past six games Game Rushing yards Week 14 (vs. Seahawks) 156 Week 15 (vs. Texans) 138 Week 16 (@ 49ers) 92 Week 17 (@ Titans) 83 Wild Card Game (vs. Bills) 155 Divisional round (@ Steelers) 164 Average 131.3 Source: NFL.com

Fournette has posted six games with 100-plus rushing yards as a rookie, and two came during that stretch. What's most impressive and reassuring for the Jaguars is how they fared without him at his best—or without him entirely.

They tore up the Houston Texans defense in Week 15, a game when the Jaguars showcased their deep stable of running backs while Fournette sat out. Three Jacksonville backs—Corey Grant, Chris Ivory and T.J. Yeldon—combined for 138 rushing yards. Yeldon, who finished Sunday with 77 yards from scrimmage and a touchdown, averaged 5.2 yards per carry throughout the regular season.

Then there's quarterback Blake Bortles, who has been far more effective when he doesn't dare to flirt with disaster by throwing the ball. He finished seventh among quarterbacks during the regular season with 322 rushing yards, and he has now run for 123 yards over two playoff games.

The Jaguars' depth at running back means they can march on if Fournette is banged up. But of course, getting the healthy version of the All-American would put the Jaguars in a better position to pursue their brand of '80s-era football against the Patriots. It's an approach rooted in defense, a clock-grinding backfield...and then more defense.

That blueprint has led to few style points but plenty of actual points during a surprising season highlighted by the Jaguars' first division title since 1999.

Now they have the pieces in place to keep plowing through the AFC gauntlet. They'll need to iron out the coverage hiccups that nearly gave the Steelers a chance at a comeback. And they'll need to rely on their running backs while hoping the Bortles who threw only one interception over a five-game stretch late in the season shows up.

But another Jaguars upset, this time as 9.5-point underdogs, according to OddsShark, isn't some impossible or laughable dream. Those two words have been attached to the thought of a Jaguars championship for a while. That laughingstock era is on its last breath now, and the plug could be pulled Sunday.