After four months of slumber, the 2016 NFL season got its unofficial kickoff Monday when the Green Bay Packers started their organized team activities, the beginning of the final phase of their offseason program.

The Packers' offseason program has been ongoing for more than a month with workouts, conditioning and meetings, but now players and coaches will get on the practice field. Organized team activities will lead into a three-day minicamp June 14-16.

Three OTAs will be open to the public before minicamp, starting — weather permitting — with an 11:30 a.m. session Tuesday (the other open OTAs are June 2 and 6).

Something you won’t see Tuesday? Half of the Packers' rookie class.

Remember, because of the NFL’s rule preventing players drafted from universities with a quarter-based schedule from participating full-time with their new team until classes end, the Packers will be without four rookies. First-round nose tackle Kenny Clark (UCLA), fourth-round inside linebacker Blake Martinez (Stanford), fifth-round receiver Trevor Davis (California) and sixth-round tackle Kyle Murphy (Stanford) fall under that rule.

Here are five things to keep an eye on when the Packers conduct their first open OTA of the 2016 season:

1. Eddie Lacy’s physique

All eyes will be on Eddie Lacy on Tuesday for one reason: Namely, how different does Lacy look compared to last season? After the season, Packers coach Mike McCarthy admitted his top running back reported to training camp last year out of shape. He was unprepared for the rigors of the fall, gaining considerable weight. Lacy spent this offseason out west, working out with P90X founder Tony Horton. The goal was to remake his body. All indications are that Lacy approached this offseason with the necessary seriousness. In pictures leaked over social media, Lacy has looked slimmer. Now, fans will get a chance to see for themselves. Make no mistake, nothing could boost the Packers' offense more than an improved Lacy.

2. Clay Matthews’ position

Be wary of reading too much into where Matthews lines up this spring. Team reps are limited in OTAs, and positional drills don’t always resemble the regular season. But it could be interesting to see how Matthews’ reps split between inside and outside linebacker. McCarthy has left little flexibility regarding what position Matthews will play in 2016: He is an outside linebacker, returning to the edge, where he can wreak havoc rushing opposing quarterbacks. But in each of the last two seasons, the Packers' needs at inside linebacker have necessitated a shift. Expect Matthews to continue getting reps at both positions this offseason, as he has in the past. What could be telling is whether his reps are overwhelming at one spot over another, especially if they lean more to inside linebacker.

3. Jared Cook’s potential

Technically, Cook’s first day came April 18 when the Packers started their offseason program. His first practice came Monday. But the first time Packers fans get to see their new tight end? That finally will come Tuesday. Cook has been an intriguing addition since the moment general manager Ted Thompson signed him in late March. He has the size and, more importantly, straight-line speed to be the threat quarterback Aaron Rodgers needs down the seams, stretching the field vertically. Little can be gleaned from these noncontact sessions in terms of actual football ability, but Cook’s athleticism and movement skills will be worth watching.

4. Jordy Nelson’s presence

For the first time since a torn ACL knocked him out of the entire 2015 season in August, Packers fans could get to see Nelson on the practice field. Nelson is gradually but consistently working his way back to the field, with training camp set as his target date to resume full-time participation. When the offseason program began, Nelson said his workload was “still up for discussion” for OTAs. He has been running, even cutting, and lifting weight. He has started to work on his route tree. Still, the Packers will be careful with Nelson’s transition back to the field. From individual reps to sideline bystander, it’s unlikely his workload will be all that surprising when fans see him Tuesday. The one exception would be if Nelson is taking a good portion of team reps.

5. Aaron Rodgers’ participation

Last we heard from Rodgers, the two-time MVP quarterback was feeling “great” after minor knee surgery a couple days after last season concluded. So there shouldn’t be any physical limitations to Rodgers’ workload, but it still will be worth monitoring. The Packers have scaled back Rodgers’ preseason throws over the past couple years, but they’ve balked at putting him under any sort of offseason pitch count. As he gets older — he turns 33 in December — it would seem likely his offseason participation eventually tapers. Keep in mind, the Packers need to use this offseason to develop second-year quarterback Brett Hundley into a solid backup. There will be no shortage of reps for Hundley. The question is how much Rodgers, who never has shied from practice, eases into OTAs.

rwood@gannett.com and follow him on Twitter @ByRyanWood

http://www.packersnews.com/sto...ackers-ota/84796666/