Head coach Doug Marrone of the Jacksonville Jaguars. (Tim Warner/Getty Images)

The Jacksonville Jaguars defied many expectations on Sunday, upsetting the Houston Texans, 29-7, in the season opener.

Not only did that win give the Jaguars a winning record for the first time since September 2011, but the team did it in exciting fashion, creating a 19-0 lead at the half — the second-largest first-half shutout margin the franchise has recorded on the road, per Elias Sports — giving them sole possession of first place in the AFC South.

The plan was simple: Limit embattled quarterback Blake Bortles’ pass attempts and instead rely on rookie running back Leonard Fournette, the fourth overall pick in the 2017 draft, and the team’s defense to deliver the knockout punch.

Bortles completed 11 of his 21 passes for 125 yards and a touchdown, but, more importantly, he didn’t turn the ball over and the offensive line didn’t allow a sack for only the second time in his career. His 21 passes were the fewest he’s thrown in an NFL game, three fewer than the 24 he attempted in a Week 3 loss to the Indianapolis Colts in 2014, a game in which he replaced Chad Henne in the second half.

Bortles also targeted seven different receivers, and will have to learn to adapt without his top option, Allen Robinson, who suffered a torn anterior cruciate ligament in his left knee, ruling him out for the remainder of the season.

The loss may not be as bad as you think. With Robinson healthy in 2016, Bortles produced a passer rating of 81.0 using three-wide-receiver sets, also known as “11” personnel, a package the Jaguars used 620 times last year, sixth-most in the league. The league average in these situations was 89.5. Yet Bortles’ passer rating on passes targeting Robinson in these situations was a mere 69.4 last season, so the loss might not be as limiting as some make it out to be when the team goes with Allen Hurns, Marqise Lee and rookie Keelan Cole in three wide receiver sets.

Blake Bortles, using “11” personnel, to: Comp% Yd/Att PsrRt
Allen Hurns (2016) 50.9% 6.7 69.4
Allen Robinson (2016) 55.3% 7.0 74.9
Marqise Lee (2016) 60.0% 8.5 75.0
All recievers (2016) 61.0% 6.7 81.0
NFL average (2016) 64.3% 7.2 89.5

The presence of Fournette also gives opposing defenses something else to think about. Fournette ran 26 times for 100 yards — 68 after contact — and a touchdown plus caught three passes for 24 yards in his NFL debut. Fournette is the first Jaguars rookie in team history to rush for 100 yards in his debut, according to ESPN’s Michael DiRoccio. Heading into Monday night’s games, he was the fifth-highest-rated back by the game charters at Pro Football Focus, with two runs of 10 yards or more on the right side of the offensive line. The team had just four runs of 10 yards or more behind the right side all of last year.

Leonard Fournette during Weeks 1 of the 2017 regular season (sharpfootballstats.com)

While the offense was moving the ball down the field, Jacksonville’s defense was feasting off the ineptitude of the Houston Texans’ quarterback situation.

Veteran defensive end Calais Campbell was credited with a franchise single-game record 3.5 sacks, all in the first half. Yannick Ngakoue added a strip sack — he had two sacks in the game — which Dante Fowler scooped up and took all the way to the end zone. The end result: a franchise-record 10 sacks — six against Tom Savage in the first half — and five forced turnovers, making them just the fifth team over the past decade to record 10 sacks in one game.

“I feel like this is a good starting point and just build off this and take it into next week,” Ngakoue told John Reid of the Florida Times-Union. “Today we celebrate, tomorrow we focus on Tennessee. No one was really talking about us coming into this week. They were talking about the defensive lineman on the Texans. So we just came in and showed we can do.”

According to Fancy Stats’ preseason power ratings, Houston should be more difficult to defeat than the Tennessee Titans. The Texans ranked No. 12 heading into Week 1, giving Jacksonville a 21 percent chance at an upset, while the Titans ranked No. 25, making the Jags a 44 percent underdog at home. But if they can execute the same way they did against Houston in Week 1, there is no reason the Jaguars can’t open the season 2-0 for the first time since 2006.

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Even an awkward Phil Simms exchange couldn’t stop Tony Romo from acing his NFL opener for CBS

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Correction: Photo credit listed Gus Bradley as head coach. This has been fixed.