Rutgers defensive tackle Darius Hamilton felt "like an outcast" early last season.

Immediately following a serious knee injury -- one that kept him out for 11 games -- the team captain fell silent, fearing no one would respect the opinion of a defender who couldn't play. He spent nights worrying about his NFL future and his team. Sometimes, at the very beginning, he said he just wanted to shut the outside world out.

"When something like that first happens, it's hard to stay positive," Hamilton told ESPN.com, "especially because I thought I would be training [for the NFL] right now. So it was definitely a setback; now, it's just a minor setback."

Hamilton's knee still isn't 100 percent, but the fifth-year senior promised he's not looking back anymore. After all, he's got plenty of reasons to stay positive now. He never thought he'd be able to play this spring -- "If you told me that at the end of the season, I would've called you a liar" -- so he's grateful just to be back on the field.

He's been forced to wear a green non-contact jersey this spring. But he can still take part in drills, he can still run, and he can still practice. It's progress. He bent over after Day 1, breathing so heavily that drool hung from his mouth, but the upbeat New Jersey native is slowly getting back into football shape after his unspecified injury.

"Everything happens for a reason," Hamilton said. "There's a lot of good that came out of me not being able to play. I became more of a student of the game, I gained more weight, I'm a lot stronger and, just to be able to play this game with my guys again, it's all really exciting."

In the last game Hamilton played, in the 2014 Quick Lane Bowl, he weighed in at 255 pounds. He's now up to 283 pounds -- and he wants to play this season between 290 and 295.

With a defensive-minded head coach in Chris Ash, Hamilton is optimistic he won't have to sacrifice quickness for strength. The two spoke shortly after Ash's hiring, and they immediately found common ground on Ash's vision of a hard-nosed team with no quit. Hamilton trusted him.

But, even if he didn't, Hamilton still wouldn't have exercised his right to play elsewhere as a graduate transfer. His team refused to abandon him during his injury and, likewise, Hamilton was adamant he didn't once think of leaving them behind.

When his roommates would catch Hamilton feeling down about his injury, they would crack a joke. When Hamilton wondered if anyone cared what he had to say, his teammates let him know he was still a crucial part of Rutgers. And when Hamilton "wanted to curl up in a ball," they assured him everything would turn out all right.

"I think, in the generation we live in, a lot of people are scared to talk about love," Hamilton said. "But, in tough times, I think love is one of those things that really gets you going -- and I had it on both the family- and friend-front."

According to published reports, Hamilton hobbled around practice Tuesday with a noticeable limp. But he knows the worst is over. He's setting his sights on summer as a crucial time to increase his weight, understand new concepts and strengthen his knee.

This wasn't Hamilton's original plan. He was supposed to be preparing now for the NFL draft and for saying his final good-byes to Rutgers. But he's staying positive. And he can't wait to see what comes next.

"There are a lot of things that worked out for me, and I'm just looking at the future, man," he said. "I'm definitely seeing brighter days ahead."