DETROIT — The Packers don’t know when and they don’t know how, but every season there comes a moment when a young, unheralded player does something miraculous.

On Sunday night, undrafted rookie receiver Geronimo Allison and second-year fullback Aaron Ripkowski were those guys for Green Bay.

Allison and Ripkowski weren’t the names on the tip of everyone’s tongue going into the Packers’ NFC North showdown with Detroit, but their performances played a critical role in Green Bay pulling out the 31-24 victory at Ford Field and clinching their fifth division title in six seasons.

Allison caught four passes for a team-high 91 yards, while Ripkowski produced a career-high 76 yards on 11 touches. Each player caught a touchdown pass from quarterback Aaron Rodgers.

While veterans such as Rodgers and receiver Jordy Nelson often get the glitz and glamour, someone unexpected usually makes his presence felt during playoff runs.

“It’s one of the most exciting things to watch,” said Nelson, who finished with six catches for 66 yards. “We tell the young guys when we start the season … you’re going to help win games for us, especially down the stretch. We know injuries become a factor in the playoffs.”

Allison was once again called upon to lend a hand on offense with veteran receiver Randall Cobb sitting out with an ankle injury. Once again, he responded when called upon, similar to last week’s four-catch, 66-yard performance against Vikings.

Allison’s first catch against the Lions couldn’t have come with better timing. Shortly after Detroit pulled ahead 14-7 late in the first half, the 6-foot-3, 202-pound receiver made a 39-yard grab to help set up a Mason Crosby 53-yard field goal before halftime.

With the Packers clinging to a 17-14 lead going into the fourth quarter, he then caught another 31-yard pass on first-and-16 before laying out at the end of the series to grab a 10-yard touchdown pass from Rodgers to give Green Bay a 23-14 lead.

Allison signed with the Packers as an undrafted free agent out of Illinois in May to little fanfare. However, it didn’t take long for Green Bay’s receiver to see he could be a difference-maker.

“I knew that he was special the day he came in,” said running back Ty Montgomery, who rushed for 44 yards on eight carries. “A lot of talk has been about me and my journey, but ‘G-Mo,’ as we call him, he’s been on a journey, too. Undrafted, started the year on the practice squad, and look where he is now.

“He’s a faithful kid – I’m saying kid like I’m that much older than him – but ‘G-Mo’ is a great dude and I’m super happy for him that everything is coming together.”

A sixth-round pick in 2015, Ripkowski shadowed veteran fullback John Kuhn during his rookie season before the Packers anointed him as their starting fullback this past summer.

Ripkowski took that responsibility seriously, and over the course of the season, wanted to show the coaching staff he was up to the task of filling the three-time Pro Bowler’s shoes.

Along with being a capable blocker, he’s shown a knack for running the ball. Operating in concert with Montgomery, Ripkowski gained 45 of his 61 rushing yards in the first half.

Furthermore, he caught his first receiving touchdown from 7 yards out to get the Packers on the board in the second quarter. All told, the Packers finished the game with 31 carries for 153 yards (5.1 yards per attempt).

“It’s nice to get a little change of pace and change of speed,” said Ripkowski of working with Montgomery. “Because obviously Ty isn’t a power back like me but he has strength, and I’m not nearly as fast as he is so it’s good to get a change of pace and keep the defense guessing.”

The Packers also got their usual contributions from their established playmakers. Rodgers threw for 300 yards and four touchdowns, with receiver Davante Adams catching his two other touchdown passes.

What the Packers have learned during their six-game winning streak is you never know who’s going to step up in a given week. With the NFC North on the line Sunday, Allison and Ripkowski didn’t shy away from the opportunity.

“It’s a blessing,” Allison said. “I say that time and time again. It’s a blessing to be in this locker room and be with this organization, and make plays, and play under Aaron – it’s a blessing. I can’t say that enough.”

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