By Paul Imig Special to OnMilwaukee.com Published Jul 20, 2015 at 1:06 PM

As NFL training camp approaches, we’ve been counting down the most important players for the Green Bay Packers this season.

If you missed the list of which offensive players will mean the most to the Packers, make sure to go back and read that. Today, we conclude the list of defensive players who will play critical roles for Green Bay.

No. 5: B.J. Raji / Letroy Guion, nose tackles

Age/experience: Raji: 29 / 7th NFL season; Guion: 28 / 8th NFL season

Stats last season: Raji missed due to torn right biceps; Guion: 41 tackles, four tackles for loss, one forced fumble and 3.5 sacks

Expectations for 2015: It doesn’t really matter which of these two nose tackles performs well for the Packers. As long as either B.J. Raji or Letroy Guion have a quality season, Green Bay’s defense should be solid upfront. Last year, Guion was brought in to be Raji’s backup. This year, it will be a battle to see which big man earns more snaps. Raji and Guion are both on one-year contracts, so there will be plenty of motivation between them. Being in their late-20s, they are at a critical stage of their careers. A good season could get them a multi-year contract next offseason. A bad season could force them into another one-year deal – or inch them towards retirement.

Injury history/position depth: Raji needs to show he can bounce back strong from the torn right biceps that cost him the 2014 season. Guion was healthy enough to play in every game last season. The only other true nose tackle on the roster is Mike Pennel, who performed fairly well as an undrafted rookie. If Raji and Guion are both healthy entering the regular season, Pennel will have to prove there’s a reason to keep him around.

No. 4: Casey Hayward, cornerback

Age/experience: 25 / 4th NFL season

Stats last season: 47 tackles, three interceptions, two tackles for loss, zero forced fumbles and zero sacks

Expectations for 2015: The free-agent departures of Davon House and Tramon Williams will thrust Casey Hayward from rotational backup to starting outside cornerback. That’s a significant jump, but it’s one that position coach Joe Whitt feels confident Hayward can handle. Hayward has proven to be a ballhawk, but his level of responsibility is going to be higher than it’s ever been. Hayward and Whitt downplayed the transition from playing mostly in the slot to playing outside, but that will be the top thing to watch with him all season. On the last year of his rookie contract, Hayward will have to show he’s worthy of a contract extension and of being a long-term starter.

Injury history/position depth: A foot injury kept Hayward sidelined throughout organized team activities and minicamp. The expectation is that he’ll be ready for training camp. A hamstring injury cost Hayward 13 games in 2013, but he was healthy for every game in his other two NFL seasons. A group of inexperienced cornerbacks (Demetri Goodson, Damarious Randall, Quinten Rollins) wait behind Hayward.

No. 3: Mike Daniels, defensive line

Age/experience: 26 / 4th NFL season

Stats last season: 47 tackles, three tackles for loss, zero forced fumbles and 5.5 sacks

Expectations for 2015: Mike Daniels is the only sure thing Green Bay has on its defensive line. Daniels has been consistently productive and has seen his playing time go up every season: from 25.6 percent of snaps as a rookie to 48.6 percent of snaps in 2013 to 63.9 percent of snaps in 2014 (according to data from ProFootballFocus). This season, Daniels should find himself even more involved. Like Hayward, it’s a contract year for Daniels. As one of the league’s most promising up-and-coming defensive linemen, Daniels could be on the verge of a big pay day.

Injury history/position depth: Daniels has had a healthy NFL career so far. Behind him, none of the Packers’ other defensive linemen can do what Daniels can. Datone Jones and Josh Boyd have NFL experience, but they’re somewhat limited in their respective skill sets. Second-year player Khyri Thornton and rookie Christian Ringo should both get opportunities.

No. 2: Sam Shields, cornerback

Age/experience: 27 / 6th NFL season

Stats last season: 44 tackles, three interceptions, one tackle for loss, zero forced fumbles and zero sacks

Expectations for 2015: There will be a lot on Sam Shields' plate this season. He always had Williams to rely on opposite him, but Shields now finds himself as the veteran of the group. If Shields struggles, it will be difficult for Green Bay’s secondary to be successful. He’s going to be that important to the defense. Shields will likely draw a lot of matchups against top wide receivers, meaning a couple showdowns with Detroit’s Calvin Johnson and Chicago’s Alshon Jeffery. Shields is in the second year of a four-year contract that could pay him a total of $39 million, so he’s being compensated like a top-tier starting outside cornerback.

Injury history/position depth: Shields has yet to have a full healthy season in the NFL and has missed 10 games over the past three years. The same inexperienced group that waits behind Hayward is also waiting behind Shields. If he misses a game or two, the Packers might be fine. But, unlike in the past couple seasons when there was more proven depth at cornerback, a month-long injury to Shields could be costly to the defense.

No. 1: Clay Matthews, linebacker

Age/experience: 29 / 7th NFL season

Stats last season: 71 tackles, one interception, seven tackles for loss, two forced fumbles and 12 sacks

Expectations for 2015: Clay Matthews has always been important to Green Bay’s defense. However, he’s never been more important than he is now. A case could be made that few defensive players in the league mean as much to their team’s success in 2015 than Matthews will. The midseason position change to inside linebacker wasn’t a temporary fix. Matthews lined up at inside linebacker in multiple packages during OTAs and minicamp. He thrived at that spot late last season and has now really embraced the change. Matthews’ versatility and ability to make disruptive plays from anywhere on the field will be key to the Packers having a better defensive season than they did a year ago.

Injury history/position depth: Matthews has been somewhat injury-prone throughout his career, but he played in every game last season. Playing inside linebacker should require less strain on his body given that he doesn’t have to run into offensive tackles on an every-play basis. There’s no experienced depth behind Matthews at inside linebacker. Rookie Jake Ryan and second-year player Carl Bradford would be next in line, but it’s doubtful that either is ready yet to produce at a high level. There’s more depth at outside linebacker, with Julius Peppers, Mike Neal, Nick Perry and Jayrone Elliott all able to contribute.

Paul Imig Special to OnMilwaukee.com
Paul Imig spent the past five years working for FOX Sports WI. He began by covering the Milwaukee Bucks and Milwaukee Brewers before taking over the Green Bay Packers beat in 2011. In addition to his writing, Paul also made television appearances nationwide on FOX Sports 1. He can be heard on the radio statewide on The Bill Michaels Show and can be seen on Time Warner Cable's Roundtable show with Dennis Krause. Paul is the 2015 recipient of the University of Wisconsin-Milwaukee's award for Graduate Of the Last Decade (GOLD).