GREEN BAY — Rarely does an NFL season play out exactly how a team expects it will on paper. Injuries happen. Game plans are altered. New weapons must emerge.

At the start of the Packers’ 2016 season, few would have predicted Ty Montgomery making an in-season conversion to running back, LaDarius Gunter leading all cornerbacks in snaps or Davante Adams breaking out the way he has.

However, that’s the way the NFL works. Every year, it falls upon the team’s second- and third-year players to take the next step and assume more responsibility.

This season has been no exception in Green Bay, where 19 players from the Packers’ 2014 and 2015 rookie classes have combined for 207 games played and 107 starts this year.

The impact can be felt in all three phases, but the most unexpected production has come on the offensive side of the ball with Montgomery, a former receiver who took the reins at running back after Eddie Lacy’s season-ending ankle injury.

A third-round pick in 2015, Montgomery officially was given a new job title leading up to the Packers’ Week 15 matchup with Chicago. He responded with 162 rushing yards and two touchdowns.

“One of the things I was really impressed with during that game was his instincts as a runner,” running backs coach Ben Sirmans said. “There were times where he appeared to be bottled up and he understood how to set up his blocks, and interpret where the hole was probably going to be.

“He almost looked like a seasoned vet from that standpoint.”

While converting players to new positions is unique, the general script has been the same for the Packers and their draft-and-develop system. It’s almost a rite of passage for second- and third-year pros to break out on a roster with an average age of 25.

Getting Jordy Nelson back from injury has played a major role in the league’s fifth-highest scoring offense, but Adams’ improved health and rapid development has given quarterback Aaron Rodgers another weapon in the vertical passing game.

During Saturday’s 38-25 win over Minnesota, Nelson and Adams became only the second receiving duo in team history to each surpass 10 touchdown catches in the same season. It came two seasons after Nelson and Randall Cobb were the first to do so.

Cobb has been dealing with an ankle injury that sidelined him against the Vikings. He sat out of practice on Wednesday and Thursday with the hope the added rest might help increase his chances at playing against Detroit.

“We’d love to get Randall back this week to get everybody back, but we’ve seen a lot of different guys step up,” said Rodgers this week. “Almost a different guy every week with Jordy obviously this last week, Ty the week before, Davante had a big game, Jared (Cook) had a big game in there. There’s a number of different guys who have played big roles for us.”

Defensively, the Packers have been tested since the regular-season opener in Jacksonville when Pro Bowl cornerback Sam Shields sustained a concussion that eventually landed him on injured reserve.

Only two of the 11 defensive players the Packers started against the Jaguars in Week 1 have yet to miss a game this year: defensive tackle Mike Daniels and safety Ha Ha Clinton-Dix.

Clinton-Dix, a first-round pick in 2014, recently was selected to his first Pro Bowl in the midst of recording 73 tackles, five interceptions and one forced fumble to power his third NFL season.

Meanwhile, Gunter has led all Packers’ cornerbacks with 794 defensive snaps this year after entering the season as the fifth option at cornerback behind Shields, Damarious Randall, Quinten Rollins and Micah Hyde.

“We had some injuries throughout this season, but guys like that are what keep us going,” Hyde said. “Ha has been playing the best football he’s ever played. ‘Gunt’ is out there doing his thing and playing his best football, and doesn’t get any credit for it. Guys like that, that’s who you want to be around. That’s who you want to be out there playing with.”

Forty-six of the 53 players on the Packers’ current roster are homegrown prospects, whose NFL careers started in Green Bay. Their contributions have been endless, especially in the face of injury.

Corey Linsley (2014, fifth round) has been Rodgers’ starting center for the past eight games after JC Tretter sustained a knee injury in Week 8 in Atlanta. At the same time, Jake Ryan (2015, fourth) and Joe Thomas (2014, undrafted) have helped settled down the situation at inside linebacker after years of change.

Aaron Ripkowski (2015, sixth) has developed into a powerful and trustworthy fullback who was named an alternate for the Pro Bowl, while Richard Rodgers (2014, third) is part of a solid one-two punch at tight end with veteran Jared Cook.

Things didn’t quite turn out as planned for the Packers this season. Yet, it’s been the production from their 2014 and 2015 rookie classes that has helped Green Bay win its last five games en route to Sunday’s NFC North showdown with the Lions.

While there are numerous playoff scenarios in play – including one that sees Green Bay clinch a playoff spot with a Washington loss to the New York Giants – the young nucleus of the Packers’ roster has its own business to take care of.

“We need to win,” said Adams, who needs 34 yards against Detroit for his first 1,000-yard season. “You don’t want to rely on other teams to lose.

“I don’t even want to watch the game before that to see what happens. That might change the way you play subconsciously. We want to go in and try to win that ball game.”

Class contributions

2014: S Ha Ha Clinton-Dix (15 games, 15 starts), WR Davante Adams (15 games, 14 starts), TE Richard Rodgers (15 games, six starts), C Corey Linsley (eight games, eight starts), LB Joe Thomas (15 games, six starts), WR Jeff Janis (15 games, one start), LB Jayrone Elliott (11 games), CB Demetri Goodson (six games, three starts), DL Mike Pennel (eight games), WR Jared Abbrederis (five games), LB Carl Bradford (four games).

2015: CB Damarious Randall (nine games, eight starts), CB Quinten Rollins (13 games, 10 starts), RB Ty Montgomery (14 games, five starts), CB LaDarius Gunter (15 games, 14 starts), LB Jake Ryan (13 games, 10 starts), FB Aaron Ripkowski (15 games, seven starts), DT Christian Ringo (eight games), QB Brett Hundley (four games).