GREEN BAY, Wis. -- Jeff Janis got the NFL equivalent of a call to the principal’s office.

It came after a poor performance on special teams, the place where a young Green Bay Packers player must make his mark first. Janis found himself seated in coach Mike McCarthy’s office following last summer’s preseason game at Pittsburgh.

Jeff Janis broke out with 145 yards receiving and two touchdowns in the Packers' playoff loss against Arizona. Matt Kartozian/USA TODAY Sports

“He didn’t play very well on special teams,” McCarthy recalled last week at the NFL scouting combine in Indianapolis. “I can remember specifically, I had him in my office after the Pittsburgh game because of his performance on special teams.”

More than six months later, McCarthy can say without hesitation that Janis “became clearly one of our better special-teams players.”

Despite what looked like a breakout performance in the playoff loss at Arizona, he still has a way to go as a receiver, especially in a complex NFL offense where receivers must read defenses the same way the quarterback does.

At the combine last week, one coach described Janis’ experience level coming into the NFL like this: In college at Saginaw Valley State, Janis was told to run deep and out-jump everyone. Developing Janis into a precise route-runner will be one of receivers coach Luke Getsy’s biggest challenges.

“[Janis had] particularly a difficult time catching the ball over his shoulder,” McCarthy said. “He kind of has a stiffness there, and Luke, he took that on about Week 7 there after the bye week, and you could see him improve. He just needs things like that. You only get so much time with your players compared to prior years, but I’m hoping he takes another big step.”

The playoff loss at Arizona, where Janis nearly saved the day with seven catches for 145 yards (including the 41-yard Hail Mary touchdown at the end of regulation) showed the kind of potential he has as a big-play receiver. It also opened McCarthy up to questions about whether he should have employed Janis on offense more than the 129 snaps the second-year receiver got in the regular season.

McCarthy clearly didn’t think Janis was ready. He played him largely out of necessity against the Cardinals after Randall Cobb’s lung injury.

“I like to look at Jeff as kind of an ascending Green Bay Packer,” McCarthy said. “I look at his years, I think you look for a guy to take a jump in his second year, and clearly, you look at his rookie year -- very raw, raw player. He made the 53 on potential, not on performance.”

Janis’ big game in the playoffs actually leaves general manager Ted Thompson in a bit of a quandary. If he thought he needed another receiver, perhaps Janis changed his mind. However, there’s a danger in putting too much value on a performance like Janis had in the playoffs.

“Great kid, hard-working, very powerful,” McCarthy said. “But there were just a lot of things, when he does them, they’re for the first time. Hopefully we’re out of that phase of his development. I look for Jeff to take that next step. He made the step in your second year that you look for. He did it first on special teams.”