Thousands of players have come and gone throughout the 94-year history of the Packers-Bears rivalry. But there’s been quite a drastic roster overhaul in Chicago recently, adding dozens of new faces into the mix and removing just as many.

Aaron Rodgers barely recognized the Bears’ defense. There’s only one projected defensive starter (Shea McClellin) who was with Chicago prior to the 2014 season. Plus, there’s now a 3-4 system in place under new coordinator Vic Fangio.

With Game No. 191 all-time coming up Sunday at noon between the Packers and Bears, here are five things to watch.

1. An offense without Jordy Nelson

The Packers will have 16 regular-season games to adjust to life without Nelson. But the early stages of that process could be challenging.

Nelson drew a lot of attention on the outside, with safeties often providing help over the top. As a result, Nelson helped create better looks for other receivers to get open. With Nelson sidelined due to a torn ACL in his right knee, Green Bay’s offense won’t have that luxury during the 2015 season.

That makes Randall Cobb the top threat to Chicago’s secondary, but he’s dealing with a sprained AC joint in his shoulder. That means Davante Adams, only 22 years old, will have to win his one-on-one battles on the outside, and James Jones will have to show that he still has plenty left in the tank at age 31. If Ty Montgomery or Jeff Janis play meaningful snaps, they’ll have to give Rodgers good reason to trust them. It also could thrust Richard Rodgers to the forefront of the Packers’ passing attack.

The Bears’ secondary is among the weakest in the NFL, but this game will be the first step in Green Bay showing how its offense will function without Nelson.

2. Same old Jay?

Jay Cutler didn’t get a true fresh start this offseason, with the Bears opting not to trade their much-maligned quarterback. Cutler did, however, get a new offensive coordinator (Adam Gase) and quarterbacks coach (Dowell Loggains).

Mike McCarthy believes those two are already paying dividends for Cutler.

"I think his mechanics and some of the things that (Cutler) has shown in the preseason is an improvement over the past," McCarthy said this week.

Cutler noted that Loggains emphasized mechanics leading into the 2015 season. Cutler added, "I think this system kind of takes care of that stuff, as well, with our reads and our progressions, how we run things. It cleans up a lot of things for you."

In his career against Green Bay (including one game in 2007 while a member of the Denver Broncos), Cutler has thrown 14 touchdowns and 21 interceptions for a 67.1 passer rating.

So, will Cutler, as Charles Woodson once put it, be the "same old Jay," or will his improved mechanics lead to better results for the Bears?

3. Defending Martellus Bennett

Bennett is 6-foot-6, 273 pounds. That’s the same height as Rob Gronkowski, and eight pounds heavier than the Patriots’ star tight end. Bennett’s production isn’t at Gronkowski’s all-world level, but he’s still a matchup nightmare for Green Bay’s defense.

"He’s just a monster," Cutler said of Bennett. "I mean, he’s a big dude. He’s a hard cover. If it’s a linebacker, he’s probably going to run past you. If it’s a (defensive back), he’s just so much bigger than everybody. You just kind of throw it up, and you’re going to get a (pass interference) or he’s going to come down with it.

"And he’s a really smart football player," he continued. "He knows the Xs and Os. He knows where the soft spots are. He does a lot of studying on his own. He wants to be better than he is right now, which is a good thing for us because he’s really, really good at this point."

Clay Matthews is the only Packers player who’s big enough and athletic enough to hang with Bennett. The problem for Green Bay is, if Matthews drops back in coverage, then he’s not rushing after Cutler.

Defensive coordinator Dom Capers will need a group effort to contain Bennett. And that still might not be enough to stop Bennett from replicating the nine-catch, 134-yard performance he had against the Packers the last time these two teams met at Soldier Field.

4. Eddie Lacy’s touches

Lacy averaged 13 carries during the first eight games of the 2014 season. Over the final eight games (playoffs included), he had 19.5 carries per game.

McCarthy clearly has a strategy that he believes works best to keep Lacy fresh for January. But without Nelson, Green Bay could consider leaning more heavily on Lacy early in the season while Cobb, Jones and Adams adjust to their heightened roles.

Lacy is the second-most important piece to the Packers offense. Now more than ever, they can’t afford to have him banged up come playoff time. But Green Bay also has to win games in the meantime, and more touches for Lacy helps accomplish that. It will be an interesting balancing act for new offensive play-caller Tom Clements.

5. Special teams

The Packers had the worst special teams in the NFL last season, according to Rick Gosselin’s respected annual rankings. Tim Masthay was the worst punter in the league, based on the ProFootballFocus ratings system. Special teams played a significant role in Green Bay’s collapse in the NFC Championship Game.

All of that – and more, such as the seven blocked kicks – resulted in Shawn Slocum’s firing as special teams coordinator. But in preseason, the promoted Ron Zook hasn’t eased any concerns that the Packers will be much better in this area.

Part of McCarthy’s reason for giving up play-calling was to spend more time with special teams. Yet, Green Bay had an eight-penalty game in preseason, and Masthay was ranked by ProFootballFocus as 45th out of 51 punters who got work during exhibition football.

This will be the first chance to show that special teams won’t be a problem yet again for the Packers.