STATE COLLEGE, Pa. - One day of the summer of 2013 still sticks out for Carl Nassib. The defensive end was worried because he had yet to pay his Penn State tuition.

"I walked up to Bill O'Brien's office and I was like 'crap, I'm not going to be able to practice,' " said Nassib, who started his Penn State career as a walk-on. "And he said I was on scholarship. That was pretty intense."

The West Chester native said he's thankful every day to be a part of Penn State's defense. While many dread practice, Nassib said it's his favorite part of the day. And it shows.

At a practice last Saturday, Nassib could be seen - and heard - cheering on his teammates.

And, at a news conference a few weeks ago, coach James Franklin also appeared excited to see what Nassib could contribute to the Lions squad next season.

Franklin said Nassib had a "sneaky, quiet, really successful year" in 2014. And, with defensive ends C.J. Olaniyan and Deion Barnes gone, it appears Nassib has a chance to receive more playing time and potentially fight for a starting spot.

The 6-foot-7, 277-pound Nassib played in 12 games and made seven tackles last season.

But, when he was a senior at Malvern Prep, Nassib said he was thinking more about attending medical school than playing college football. Everything changed after he sent Penn State his highlight tape. The opportunity to play there, even as a walk-on, was an offer he couldn't turn down.

Nassib came to Penn State in the fall of 2011, standing 6-foot-5 and weighing 218 pounds. Yet he said his confidence never wavered, even as he went up against larger and more experienced players each day at practice.

"You can't second guess yourself or you'll get pummeled by 300-pound guys," he said with a laugh.

While he still hopes to become a pediatrician, the biology major has solidified his passion for football over the last four years.

"I just followed in the footsteps of Jesse Della Valle and Ryan Keiser, who are great role models for me, to try and represent walk-ons," Nassib said. "It shows hard work, because it's not easy being a walk-on."

As he gears up for the 2015 season, Nassib said he's looking forward to having the same defensive coordinator for the first time in his Penn State career, and to step into a larger role.

"I just have been trying to fill in a leadership role like Deion and C.J. had on the D-line," Nassib said. "They were very great role models for us."