JACKSONVILLE, Fla. -- Playoff-mode Blake Bortles showed up on Sunday for the Jacksonville Jaguars against the New York Jets.

Bortles threw for a career-high 388 yards and two touchdowns in the Jaguars’ 31-12 victory in front of 65,353 at TIAA Bank Field. He completed his first 11 passes, threw one away to avoid a sack, then connected on his next five in the first half.

It was a bounce-back performance for Bortles, who didn’t play well in a 9-6 loss to Tennessee a week earlier, and it was reminiscent of the way he performed in the 2017 playoffs. The only negative play was a throw tipped at the line of scrimmage by linebacker Avery Williamson and intercepted by cornerback Darryl Roberts.

Other than that, it was just what the Jaguars (3-1) needed before back-to-back road games at Kansas City and Dallas. It’s also what the Jaguars need from Bortles at least the next few weeks -- and possibly longer -- because he might have to carry the offense after injuries to running back Leonard Fournette and center Brandon Linder.

“Just seeing Blake command the troops and get everybody lined up and focused and ready and just ... he’s out there like a surgeon, just precisely throwing great passes, leading the troops, making the right calls,” defensive end Calais Campbell said. “It’s amazing see him maturing into this incredible quarterback.”

Fournette experienced hamstring tightness late in the first half and was pulled from Sunday's game. He had missed the previous two games with the injury, which he suffered late in the first half of the season opener against the New York Giants. Fournette went back into the game shortly afterward, but the team decided to shut him down for the second half.

Even if it was just a precautionary move -- which seems likely, considering the Jaguars were ahead 16-0 at halftime and dominating the Jets (1-3) -- it’s still troublesome. Maybe sitting Fournette for the second half will be enough to ensure that his hamstring doesn’t sustain further damage and become a chronic issue.

Blake Bortles set a career high with 388 passing yards as the Jaguars improved to 3-1, beating the Jets. Reinhold Matay/USA TODAY Sports

“I’d be bulls----ing if I said no [he wasn’t concerned],” coach Doug Marrone said. “Any time you come back and you get ready to go and all of a sudden you get injured again, it’s not a good sign.”

It’s unclear how serious Linder’s injury is, though he was in the locker room after the game and told reporters he was fine. He is also managing a chronic knee injury that he suffered in the preseason and he does not practice on Wednesdays. He has been their best offensive lineman, and that unit is already down one starter after left tackle Cam Robinson's season-ending knee injury. Right guard A.J. Cann is dealing with a right triceps injury, and right tackle Jermey Parnell is dealing with a chronic minor knee injury.

Not having Fournette and Linder had an obvious impact on the Jaguars in the second half against the Jets. Instead of feeding Fournette the ball to eat up clock and salt the victory away, the Jaguars relied on T.J. Yeldon (who fumbled, which led to a Jets TD) and short passes. Receiver Dede Westbrook fumbled one of those away, too, inside the red zone.

It’s unclear how long those injuries could keep Fournette and Linder out of the lineup. That’s why Bortles -- who is now second on the franchise's all-time passing yardage list (16,003) -- has to consistently play the way he did for much of the game against the Jets. He doesn’t need to throw for 300 yards each week, but the offense has to run through him instead of the run game. He needs to be efficient, take shots down the field when they get the right look and not turn the ball over.

He did that on Sunday, connecting on a throw down the sideline to Donte Moncrief for a 67-yard touchdown. The Jaguars didn’t have a single offensive play that gained more than 19 yards against Tennessee. They had eight against the Jets -- and Bortles was involved in all of them (seven passes and a 23-yard run).

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“Talking about it throughout this past week, I really wanted to push the ball down the field and make up for not doing it last week,” said Bortles, who moved into second place on the franchise’s all-time passing yardage list (16,003), passing David Garrard and behind only Mark Brunell. “I think it was coming along and the big thing this week was just emphasizing only take it if it’s there. You do that because that’s exactly what they’re trying to do to kind of bait you into throwing one into some coverage. When you get the ball to Corey [Grant], T.J. [Yeldon] and some of these guys in space it’s a 10-15 yard gain every time, so it’s just positive getting a big chunk.”

He needs to be quarterback who led the Jaguars to the AFC title game in January.

“I think he’s done a nice job, and the receivers were able to get open,” Marrone said. “They were able to run away. They dropped some coverages on our guys and we were able to deliver the ball. The line was able to protect. When you’re out and we’re struggling at running back, with our running backs a little bit, then obviously somewhere else you’re going to have to pick up in your game. We were able to do that.

“You’d like to be able to get those throws and those passes and open things up a little bit more. It keeps people from putting all those guys in the box.”