JACKSONVILLE – An NFL scrimmage isn't what it once was, but it's still pretty cool.

That's particularly the case around the Jaguars this season, because when they hold their mock game/scrimmage at EverBank Field at 6:45 p.m. Saturday, the state-of-the-art video boards will be in action. And those video boards? Well, they're worth a look; they're big and they're cool.

Very, very cool.

The scrimmage/mock game will be, too. Not that it's a scrimmage, exactly. There won't be four quarters of full-on, to-the-ground tackling. That doesn't happen in NFL preseason scrimmages anymore, and it won't really be close to that.

But the Jaguars' coaches will get players into game-like situations, and there will be one-on-one competition, blocking and tackling – and live action. There also will be fans, lights and more energy than a typical morning training camp practice, so it's something players anticipate.

Jaguars Head Coach Gus Bradley called it "a pregame rehearsal for our first preseason game."

"In a way, it's a mock game, but you'll see some really competitive situations," he said.

Here's a look at five storylines to watch in Saturday's mock game scrimmage:

1. Blake Bortles.He's not starting, and that won't happen soon, but there's little doubt the rookie No. 3 overall selection is the primary storyline whenever the Jaguars take the field. Bortles likely will take repetitions at quarterback exclusively with the second team Saturday, something he has done throughout training camp thus far. He has looked more consistent during training camp than he did in the offseason, showing good pocket presence and better knowledge of the offense. He's improving, and Saturday will be his first "live" snaps inside the stadium the Jaguars hope will be his home for a long time.

2. Chad Henne.Remember him? The Jaguars' starting quarterback? When people talk quarterbacks around the Jaguars this offseason the conversation naturally has turned to Bortles, but Henne's progress is what matters for the short term. He's playing behind a rebuilt offensive line that has multiple new parts. He also now is playing without wide receivers Cecil Shorts III, Allen Robinson and Ace Sanders and tight end Clay Harbor. Those were four of the top five or six receiving options entering training camp. Henne's experience was a huge reason he was re-signed, and he'll need to draw on that experience with what is now an even younger group of pass-catchers than before.

Henne to @a1hurns. #JagsCamp https://t.co/TRRTVrKBVq — Jacksonville Jaguars (@Jaguars) August 1, 2014

3. Are the kids alright?With Shorts, Robinson and Sanders for at least several weeks, an offseason storyline has returned – that is, a group of young reserve receivers getting an opportunity. Rookie wide receiver Marqise Lee likely will play Saturday, but with Tandon Doss also out, Lee's the only front-line receiver available. Allen Hurns, Kerry Taylor, Mike Brown, Damian Copeland … such players are going to get opportunities beginning Saturday and a few – particularly Hurns – could play key roles if injuries to the starters linger into the season.

4. New faces up front.You won't get nearly the idea about the offensive and defensive lines Saturday as you will once the Jaguars get into the preseason, but there's enough new up front that the area is worth a look. Defensive end Chris Clemons has assumed a leadership role and has looked good in practice. End Red Bryant – like Clemons, a member of the Seattle Seahawks' Super Bowl champions last season – also has emerged as a leader on the line on and off the field. That group should be vastly improved against the run, which in turn could help a pass rush that has struggled in recent seasons. Offensively, there's a whole lot of new all over the front, but watch left tackle Luke Joeckel, the No. 2 overall selection in the 2013 NFL Draft who is fully recovered from an ankle injury that ended his rookie season after five games. He and free-agent guard Zane Beadles are the future on the left side of the offensive line and Saturday is their first "live" action as a duo.

5. Speed on defense.The Jaguars wanted to get bigger, deeper and faster on defense in the offseason. It will be tough to see the impact of the size and depth on defense in a mock game, just as it will be tough to appreciate newly signed running back Toby Gerhart in a controlled environment. But you should be able to see a significant increase in speed. A player such as rookie linebacker Telvin Smith, who is working with the first team in nickel situations, is one reason. Another is the secondary. With players such as safety Johnathan Cyprien and cornerback Dwayne Gratz having good camps, the defensive backfield is growing into a strong unit, and the secondary's speed and quickness to the ball has improved significantly over the past year.