JACKSONVILLE – The offseason program comes to an end this week.

It ends with the Jaguars' 2015 mandatory minicamp, which will be held Tuesday, Wednesday and Thursday at the Florida Blue Health and Wellness Practice Fields.

The three days not only mark the only mandatory days of the offseason program, they mark the end of Phase 3 of the offseason, a phase that also included the nine organized team activities practices held over the last three weeks. The minicamp includes the only Phase 3 practice open to the public.

That's Thursday's final practice, which will run from 9:50-11:35 a.m. The practices Tuesday and Wednesday are closed to the public and run from 9:35-11:45 a.m.

Minicamp practices are similar to OTAs. The main difference is they are mandatory whereas OTAs are not. The difference on the field is minimal. No one-on-one offense-versus-defense work is permitted in OTAs or minicamp practices, but team defense versus team offense is allowed. That means 7-on-7, 9-on-7 and 11-on-11 drills are permitted. Players wear helmets but no pads. Contact is not permitted.

After Thursday, that's it for the offseason program. The next time the Jaguars are on the field will be training camp, which will be held at the Florida Blue Health and Wellness Practice Fields beginning in late July. That makes this week a final chance to update offseason storylines such as quarterback Blake Bortles, a revamped/retooled offensive line, the offseason status of defensive end/Leo Chris Clemons and the potential impact not only of free agents such as tight end Julius Thomas, right tackle Jermey Parnell and defensive end Jared Odrick, but of a rookie class that includes several players who could make a quick impact.

Thursday's practice also will be the first chance for fans to see Thomas, Parnell, Odrick and other new free agents such as safety Sergio Brown, cornerback Davon House and Otto linebacker Dan Skuta.

Here are five players/areas to watch at 2015 mandatory minicamp.

1. Blake Bortles.A list of Jaguars offseason areas to watch must include the second-year quarterback – and he must lead the list. The work he has done on his fundamentals and mechanics has dominated Jaguars OTAs headlines – perhaps to an unreasonable degree. But he is the quarterback, so anything he says or does is big news. Bortles, the No. 3 overall selection in the 2014 NFL Draft, spent two months in California working with a team associated with quarterback/throwing guru Tom House. The primary early focus was on quickening his takeaway and pre-throw mechanics, and more focus of late has been on his follow-through. He and teammates say they can see a difference, and Bortles appears to be throwing a tighter spiral. Bortles said it's still a work in progress, though progress indeed has been made, and he said he plans to return to California for a week to work with House between the end of minicamp and beginning of training camp.

2. Allen Robinson/Julius Thomas.This list of minicamp areas to watch is offense-heavy – and in particular, it is skill-position heavy. With good reason. OTA and minicamp practices are non-padded, and therefore heavy on pitching and catching and light on blocking, tackling and the run game. But you do get a glimpse of the passing game, and you can certainly get an idea for receivers and tight ends. Thomas, a tight end who signed as an unrestricted free agent from Denver, has looked the part of the highest-profile acquisition of the offseason. Robinson, a second-year veteran wide receiver who spent the early part of OTAs rehabilitating/returning from a stress fracture in his foot, stood out last week in Week Three of OTAs, showing impressive physical ability in red-zone drills.

3. T.J .Yeldon and the running game.You can't tell everything about the running game in OTAs/minicamp, but it's easy to see even in non-contact work why the Jaguars took Yeldon No. 36 overall. He's a smooth runner with quick acceleration and the ability to ease away from defenders in the hole. On the offensive line, there's a real limit to what can be gleaned without contact, but look for a bigger group – and this week, look for some movement up front. The offensive linemen added size and bulk in the offseason while moving away from the zone-blocking approach they used the past two seasons to a gap-based scheme. New assistant head coach-offense/offensive line coach Doug Marrone said he plans to move offensive linemen around some this week to get a better idea what players can play multiple positions.

4. Chris Clemons.Clemons missed OTAs – as he is very much allowed to do under league rules. The Collective Bargaining Agreement mandates that OTAs are voluntary, and Clemons – after attending a week of OTAs in 2014 – opted to attend none this offseason. He is expected to attend this week, and while Jaguars Head Coach Gus Bradley said last week the team likely won't get him 10 repetitions per practice period, coaches do want to see where he is physically and get him work this week. Clemons – who likely will start at the Leo/defensive end positon with rookie Dante Fowler Jr. out for the season – is a 12-year veteran who often has opted to not participate in OTAs during his career, and the team isn't overly concerned about his absence. If he's in shape when training camp opens, his missing OTAs is a non-story. But for this week, his presence in Jacksonville will be news.

5. Defensive maturation.The defense was a strength at times last season – particularly up front – and reports in OTAs have been positive on that side of the ball. Fowler's absence because of a torn anterior cruciate ligament sustained in rookie camp isn't ideal, but this is a unit that could be stronger even without Fowler. The team added strong-side defensive end Odrick, Skuta, Davon House and Brown, and a group of young players who figure to be key to the core – linebacker Telvin Smith, safety Johnathan Cyprien and cornerback Demetrius McCray – could make the sort of offseason jump that often happens for young players. Defensive coordinator Bob Babich said early in OTAs the defense – in its third season in Bradley's system – was playing faster with less hesitation compared to the last two. That's what you want from a defense as players grow and become more comfortable playing in a system.