GREEN BAY — In the seconds it took for Joe Callahan to toss his backpack into his new locker on Monday, a swarm of media quickly gathered around the Packers’ rookie quarterback.

Flanked by cameras to his left and right, Callahan turned to face the crowd and loosened a surprised smile in response to all the attention he was receiving.

“I did not expect this,” Callahan said.

The same could be said for the 6-foot-1, 216-pound quarterback’s improbable rise from a standout at Division III Wesley (Del.) College to the Packers’ 53-man roster.

Perhaps the longest of long shots initially, Callahan was one of five undrafted rookies to make the Packers’ active roster after putting on a show this preseason.

Callahan capitalized on the 182 offensive snaps he was afforded during the preseason with Brett Hundley nursing a sprained ankle and Aaron Rodgers sitting out three games.

The former Gagliardi Trophy winner – an award given to the most outstanding player in DIII – threw for 499 yards and three touchdowns with zero turnovers in four preseason games.

It not only secured Callahan the Packers’ third-string job but also earned him a spot on active roster to complete his once unlikely roster bid.

“I’m really excited for him,” said Rodgers on Tuesday. “To be a DIII Heisman and come in here and show the type of improvement that he’s showed, it’s exciting.

“I think one thing that has to be really special is to go from the green mile as they used to call it, which is the back locker room, to the front locker room. Talk about an exciting time.”

After only keeping two quarterbacks on the active roster from 2009-2013, this is the third consecutive year the Packers head into a season with three on the 53.

Despite fashioning a respectable 88.2 passer rating this preseason, Callahan didn’t feel any greater sense of comfort during Saturday’s cuts.

He anxiously waited all morning to hear of his fate until finally receiving a call from Packers QB coach Alex Van Pelt. Callahan answered in a cautious manner, nervous that he’d just accepted the call to inform him he was being cut.

“He kind of caught me off-guard,” Callahan said. “He started off the phone call like, ‘Hey, what are you doing?’ Then he said, ‘Just want to let you know congrats you made the 53.’

“From then on, I don’t really remember what I said but I got the news I was hoping for.”

Callahan first called his parents to let them know he’d made the roster. He then reached out to his family and friends. What exactly was said is a blur to him, but he can recall the excitement in everyone’s voice.

Asked if he’d ever seen anything like Callahan’s situation unfold before, Packers Head Coach Mike McCarthy said, “No, not at all,” during his time coaching quarterbacks.

This preseason, McCarthy figured it would be the “Brett Hundley Show” with Rodgers unlikely to play much and the Packers slated for five preseason games.

Instead, it was the small-school standout from Absecon, N.J., who had the offense buzzing. When final cuts came due, the Packers had no choice but to keep the young quarterback.

“This is clearly Joe Callahan earning a job. How the hell is he not on your team?” McCarthy said. “I think it was clear, just watch the games, watch the video. Very happy for him personally because you always like to see a guy grab hold of an opportunity, and I thought it was very obvious what he accomplished in the preseason.”

McCarthy doesn’t care what college Callahan came from. The quarterback demonstrated a tenacious work ethic and sixth sense for maneuvering in the pocket this preseason.

He’s also adamant that Callahan making the roster has nothing to do with concern over Hundley’s ankle. The team fully expects the second-year quarterback to back up Rodgers in the Packers’ opener this Sunday in Jacksonville.

Callahan acknowledges he probably wouldn’t have been able to secure a place on the roster without the amount of reps the Packers gave him this preseason.

The rookie quarterback knows those opportunities will be cut down during the season with the Packers prepping Rodgers and Hundley for game days, but his mentality won’t change.

As exciting as the weekend was, Callahan knows he still has a lot of work ahead of him. There are goals to accomplish and it’s his job to help the team achieve them.

Was it unlikely for him to make the final 53? Maybe, but that never was the way Callahan looked at it. Since the beginning, he sought out to prove he belonged.

By the end of camp, he succeeded.

“I always made it my goal (to make the team) and never lost sight of it,” Callahan said. “Obviously I had to prove myself as camp went on and the coaches were pleased with what they saw.”

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