JACKSONVILLE – Jets-Jaguars was never small.

It got bigger five days ago.

The Jaguars this past Sunday lost an AFC South game to the Tennessee Titans at TIAA Bank Field, which is why the Jaguars enter Week 4 of the 2018 NFL season technically in second place rather than decisively in first.

That loss also is why the Jaguars' game against the New York Jets at TIAA Bank Field Sunday at 1 p.m. has a have-to feel.

Had the Jaguars won against Tennessee, they would hold a two-game AFC South lead. That would have guaranteed nothing, but it would have assured at least a one-game margin entering October.

It's not right to say the Jaguars have no room for error, because it's never accurate to say that early in an NFL season. But a loss Sunday could move the Jaguars a game behind the Titans, which would mean being a game-and-half behind because of the Titans' tiebreaker advantage.

It also would mean a second consecutive home loss after a seven-game winning streak.

Those things wouldn't end the Jaguars' season, but they're not things a team with goals of repeating as division champions and making a deep playoff run want to define September.

History favors the Jaguars Sunday. They have responded well to losses under Head Coach Doug Marrone – usually in one-sided, resounding fashion.

The Jaguars could use such a victory Sunday. They mainly need a victory, period. They need it to attain their goal of a 3-1 September, and they need it for momentum into an October that's looking somewhere between tricky and brutal.

Here are 10 things they must do to get it:

1.Respond … again. A major reason the Jaguars won the AFC South last season is they never lost consecutive games until the division was clinched. Their victories following their first four losses came by a combined 105 points. That's not just responding; that's doing so in a way that reestablishes confidence. The Jaguars need to get some reestablishing done Sunday.

2.Get ahead early. The Jets, like the Titans last week, will want to shorten the game and control tempo by running. Teams like that struggle when they're trailing. The Jaguars couldn't get a lead against Tennessee, and a potentially dominant pass rush never took over the game. Jets rookie quarterback Sam Darnold can be rattled into mistakes, but the Jaguars need to get into pass-rushing situations to make that happen. Getting ahead early is the best route into those situations.

3.Stop the run … The Jets stayed in the game against the Jaguars last season with 256 yards rushing – and they're still a big-time rushing team The Jaguars are dramatically better now in that area. They must show it.

4. … and touch him down. The Jaguars lost to the Jets last season in large part because Jets running back Bilal Powell got up and finished a 75-yard touchdown run when he wasn't touched down after falling. That play changed the early momentum – and changed the game. That must not happen again. (Obviously). Touch. Him. Down.

5.Score a touchdown defensively. Is it fair to ask the Jaguars' defense to do this every week? Of course not. Is there a chance to do this against a rookie quarterback? Of course.

6.Get the backs involved. The Jaguars' offense thrives when straining the defense with screens to the backs, then running up the middle or to the side on stretch plays with run-pass option. Running back Leonard Fournette's two-game absence has hurt. An ankle injury to backup running back T.J. Yeldon has hurt, too. Whatever the reason, this offense needs production from the backfield.

7.Get open … catch the ball. Sometimes, a group just needs to play better. The wide receivers must do that Sunday.

8.Ditto Blake Bortles. Sometimes, a player just needs to play better.

9.Test the secondary. Did the Jaguars throw underneath and to the sides throughout the Titans game rather than deep because of playcalling? Because of Bortles? Because receivers weren't open? Maybe all three. Whatever the reason, they must stretch the defense more Sunday.

10.Rattle the rookie. When analyzing this game, it always comes back to this. The Jets' defense is good enough to bother the Jaguars' offense. The Jets' running game is one of the NFL's best. If the Jaguars have a major advantage, it's the pass rush and elite secondary versus a rookie quarterback. If the Jaguars stop the run early and force Darnold into mistakes, they could have a big edge Sunday. If they don't …