Myles Jack's long-awaited return a highlight of Jaguars minicamp

Rookie linebacker Myles Jack is expected to play on third downs right away so the Jaguars can take advantage of his speed and athleticism in coverage. Robin Alam/Icon Sportswire

JACKSONVILLE, Fla. -- The Jacksonville Jaguars have a mandatory three-day mandatory minicamp Tuesday through Thursday at the practice fields outside EverBank Field. The workouts on Tuesday (9:35-11:45 a.m. ET) and Wednesday (9:35-11:45 a.m. ET) are open to the public.

Here are five things to watch for:

LB Myles Jack's return: The Jaguars' second-round pick hasn't been with the team since rookie orientation because of the NFL's graduation rule, but he was scheduled to be back in Jacksonville on June 10, and this will be his first full-team workout. He'll start out as the second-team middle linebacker behind Paul Posluszny, but eventually the plan is for Jack to be on the field on third downs so the Jaguars can take advantage of his speed and coverage abilities. That's what made him a special player at UCLA. He's so athletic and fast that he was asked to cover receiver Nelson Agholor -- an eventual first-round draft pick -- one-on-one during a game against Southern California. Watching him on the field should be fun.

WR Marqise Lee has been very good: The third-year player out of USC was the Jaguars' best receiver throughout organized team activities. Allen Robinson hardly participated because of a hamstring strain, and the Jaguars have limited Allen Hurns as he returns from sports hernia surgery, so the team's two best receivers haven't done much. That meant more opportunities for Lee, and he has taken advantage of that. He has finally been healthy for an entire offseason and looks exactly as the Jaguars hoped he would when they took him with the 39th overall pick in 2014. He looks smooth and has caught pretty much everything thrown his way. There's cautious excitement inside the building about Lee. If he can stay healthy, he adds an extra dynamic to the offense.

Spend a few minutes watching quarterback Brandon Allen: The Jaguars really like what they've seen from the sixth-round pick out of Arkansas. He has been impressive in the limited reps he has received. He had some issues early with the snap but has been accurate with his throws. He's not unseating Chad Henne as the backup, but the Jaguars view him as having a good chance to be Henne's eventual replacement. Don't be surprised if the Jaguars keep three quarterbacks on the 53-man roster.

Offensive line shuffle: It's hard to tell much about offensive and defensive linemen in a minicamp setting. The players aren't in full pads and full contact isn't allowed. But it's interesting to see players lining up at different spots. Left tackle Luke Joeckel has received some reps at guard. Right guard A.J. Cann has taken some reps at right tackle, in part because Jermey Parnell has been limited to individual work with a broken bone in his hand. Guard Mackenzy Bernadeau has moved around, too. Offensive line coach Doug Marrone said he didn't know the players as well last season, so he was hesitant to move them around as much as he has this offseason.

FS Tashaun Gipson makes a difference: I wrote last week that Gipson is the most important addition to the Jaguars' defense. For the first time in coach Gus Bradley’s tenure, he has a free safety capable of playing the position the way it’s designed, and that changes the dynamic of the entire defense. Gipson's range is impressive, which he showed off by coming from one hash to the other to pick off quarterback Blake Bortles once in the red zone. He has been in position to lay several big hits on receivers, too, which he obviously can't in OTAs, but it's evident the defense should generate more big plays with him on the field.