The Green Bay Packers and New England Patriots boast perhaps the two best quarterbacks in the NFL, but when the two teams meet on Thursday night at Gillette Stadium in Foxborough, Massachusetts, there will be little conversation about the quarterback matchup and far more scrutiny about players seeking to make the final 53-man roster on Sept. 5.

Both clubs have Super Bowl aspirations, and having quality depth beyond the top top reserves can be crucial should a team get hit by a rash of injuries. While this is just the first of four preseason games, it provides some interesting insight into how new players can perform in game situations and outside of practice.

Here's a look at some of the storylines entering the game.

Patriots Add Many New Faces

For the defending champion Patriots, training camp has become a matter of simply keeping bodies on the field. As many as 23 players have missed time during camp for various injuries, though none have been serious.

That has opened the door for a number of players to gain extra attention, particularly some of the rookies, both drafted and undrafted, at defensive end and in the secondary. All told, 10 draft picks and six undrafted free agents have participated in New England’s camp thus far, and some could play significant roles if they make the roster, according to the Boston Herald.

Head coach Bill Belichick had to account for the loss of cornerback Darrelle Revis and especially the departure of defensive tackle Vince Wilfork, and thus spent three of the team’s first four picks in the draft on the defensive line. Belichick used another two picks on the secondary, even taking a defensive back as high as the second round for the first time in 2012.

Meanwhile, two players on offense who could be immediate contributors include rookie free agents Chris Harper, a wide receiver from Cal, and David Andrews, a center from Georgia. Both should see plenty of action on Thursday.

Jordon Richards' High IQ Among Top Defense Storylines

Former Stanford standout Jordan Richards has been impressive, according to reports. Challenging both veterans Patrick Chung and Nate Ebner at strong safety, the second-round draft pick received high praise for his intelligence from teammates like starting safety Devin McCourty.

"The thing that sticks out the most about [Richards] is he’s a very smart guy," McCourty said to Comcast New England. "I think he’s a guy that is hungry. He came in day one knowing as much as possible for a rookie. The thing is we stay on him to keep playing through mistakes. He is so smart and understands so much that he hasn’t made very many mistakes."

Richards, who is listed at 5'11 and 210 pounds, put his smarts to good use when he broke up plays against Rob Gronkowski and Scott Chandler -- two tight ends that tower over him.

Defensive backs Brandon King, Darryl Roberts, and Jimmy Jean are also among the rookies getting some reps during camp. King, who went undrafted out of Auburn, has spent much of his time on special teams while Roberts and Jean flashed their potential in pass protection drills.

Along the defensive line, fourth-round pick Trey Flowers has rotated with pass rushing stalwarts Chandler Jones, Rob Ninkovich, and Jabaal Sheard, but isn’t quite in line to take anyone’s starting job just yet. The Herald reported Flowers, coming out of Arkansas, has matched the intensity and power necessary to play defensive end and batted down a pass from back-up quarterback Jimmy Garoppolo in 11-on-11 drills last week.

Surrounding Clay Matthews

The Packers too have dealt with some early injuries, but starting linebacker Clay Matthews returned to practice Monday after sitting out the first five practice sessions last week with a sore knee, according to ESPN. Green Bay head coach Mike McCarthy is calling it a “trial-return,” or rather an exercise in caution for his top linebacker.

But Matthews’ absence allowed fourth-round draft pick Jake Ryan to get first-team reps last week as McCarthy also stressed he needs to see more plays from his linebackers. There has been no shortage of praise for Ryan's dedication and toughness.

It’s believed Matthews may switch over from inside duties to the outside, and that has given Ryan and undrafted rookies Tavarus Dantzler, James Vaughters, and Jermauria Rasco a chance to earn a spot in the rotation. Third-year linebackers Sam Barrington and Nate Palmer are the likely choices to succeed Matthews, but any one of the rookies could provide much-needed depth.

Packers Offensive Line and Wide Receivers in Spotlight

The Packers also have a host of rookie offensive linemen looking to protect Rodgers, as well as several candidates at wide receiver. Undrafted lineman Vince Kowalski, Andy Phillips, Fabbians Ebbele, and Matt Rotheram are in line for reps and can certainly look to last year’s star rookie center Corey Linsley as an example of what can happen if you impress during camp. Kowalski, however, was sidelined over the weekend due to a concussion.

Then there’s receiver Myles White, who actually played in seven games in 2013 but was cut after training camp last season and re-signed to the practice squad. He has made great strides in camp. According to ESPN, White is in the midst of a nine-man battle to back-up Green Bay’s top receivers Jordy Nelson, Randall Cobb, Davante Adams, and rookie Ty Montgomery.

White, coming out of Louisiana Tech, picked up two receptions during the 11-on-11 portion of Saturday’s practice, and he’s consistently outshined second-year receivers Jared Abbrederis and Jeff Janis.