JACKSONVILLE – The wait is over. It's three days from over, anyway.

Through a long offseason, through the Senior Bowl, through the NFL Scouting Combine, through Pro Days, through the NFL Draft, through OTAs, through minicamps, through the dead zone, we've waited. And waited …

And now it's here. It's here in three days, anyway.

It's Jaguars 2015 Training Camp, which begins Friday with a 9:55 a.m. practice at the Florida Blue Health and Wellness Practice Fields. And while there are storylines for every NFL team entering every training camp, there is a significant urgency and energy around many of the storylines for the Jaguars as this year's camp approaches.

Quarterback, offensive line, running back, tight end, wide …

Well, just about every position group offensively has a critical storyline, and that's pretty much true defensively as well. Expectations are significantly higher for the Jaguars entering this season than the past two seasons, the first two under General Manager David Caldwell and Head Coach Gus Bradley.

Improvement is expected inside and outside EverBank Field, and after an offseason of significant free-agency acquisitions there's a feeling around the Jaguars that the talent level of the roster is as high as it has been in several seasons.

The work is not complete. Progress must still be made, and there are positions that must be solidified in the coming weeks. So, here are 10 things the Jaguars must do during 2015 training camp:

1.Get Blake Bortles ready.The second-year quarterback must continue learning first-year coordinator Greg Olson's offense. But there also is the matter of Bortles' release, mechanics, footwork and other fundamentals. He appeared to improve those areas beginning with his work early in the offseason with quarterback guru Tom House and continuing in the on-field offseason program. That improvement must continue.

2.Find a starting running back …The guess here is T.J. Yeldon will start the season as the feature back – and if he's not the Week 1 starter, he likely will be soon. But the rookie second-round selection from Alabama must earn the starting position; with Toby Gerhart having had a good offseason – and with Denard Robinson starting nine games last season – that's no guarantee.

3. … and sort out the rest of the running back position.The Jaguars appear deep at running back. Yeldon appears likely to soon be an every-down back, with Gerhart perhaps finding a role as a third-down back late last season. Robinson has the speed to be a weapon, and veteran Bernard Pierce and second-year veteran Storm Johnson have NFL starting experience. Entering camp it appears that Yeldon, Gerhart and Robinson are the top three, but preseason games can change running back depth charts.

4.Master the offense.The offseason was spent installing Olson's offense. Training camp will be about players gaining a deeper understanding. Bortles talked this week about wanting to gain "clear ownership" of the offense. That's probably not possible before the regular season, but how much the players own the offense by the regular season is a critical training camp storyline.

5.Stay healthy.The starting lineup appears significantly improved. The Jaguars also appear to have better depth, particularly at running back, cornerback and offensive line. But this is still a young team that can't afford to have too many ascending, young players miss preparation or early-season time.

6.Find a starting center.The Jaguars like second-year veteran Luke Bowanko, who started 14 games last season. They also like fifth-year veteran Stefen Wisniewski, who started the past four seasons for Oakland. It remains to be seen who they like better as the starter. Wisniewski was rehabilitating a shoulder injury in the offseason, so training camp will be the start of what should be a tight competition.

7.Find a starting left guard.Veteran Zane Beadles struggled at times in his first season with the team last season after signing as an unrestricted free agent from Denver. He improved late, and coaches liked what they saw in the offseason after he widened his stance and made other adjustments to adapt to the Jaguars' move toward a gap-blocking scheme. But the team selected A.J. Cann in the third round of the draft and his physical style appears to fit well with the new approach.

8.Find a starting free safety.The Jaguars signed Sergio Brown as an unrestricted free agent from Indianapolis in March and then drafted James Sample from Louisville in the fourth round in April. Free safety is a difficult find in today's NFL, and it's key in Gus Bradley's defense. The Jaguars need some combination of Brown/Sample to solidify this spot, which in turn would help strong safety Johnathan Cyprien.

9.Determine Sen'Derrick Marks' status.The veteran defensive tackle has been the Jaguars' best defensive player the last two seasons, but he spent the offseason rehabilitating a torn anterior cruciate ligament sustained in Week 17 of last season. He is targeting a Week 1 return, which would be a quick recovery time. He isn't likely to be 100 percent early in the season, and until he is, Ziggy Hood and rookie Michael Bennett will need to play well to solidify what Marks has made a productive spot on the defensive line.

10.Reset the pass rush.The defensive line last year was very productive and helped the defense register 45 sacks. But the group doesn't have a premier edge rusher, so with Marks limited early and rookie Dante Fowler Jr. out, it likely will take a group effort to reproduce last season's pressure. That's a big task, but a critical one for this defense.