HOUSTON -- If "crazy" isn’t the first word teammates use to describe Houston Texans linebacker Brian Cushing, it comes up quickly.

Crazy, intense, obsessive, focused and always up to something.

He head-butted rookie Christian Covington to congratulate him on his first sack. He drinks cold coffee blended with half a stick of butter every morning in order to ingest good fats. He pranks people all around the facility, from taping up all of Alfred Blue's belongings to leaving things on Jadeveon Clowney's chair for Clowney to inadvertently sit on.

Texans linebacker Brian Cushing collected 110 tackles this season, his first 100-tackle season since 2011. Ray Carlin/USA TODAY Sports

But shy?

“He was a little shy,” said Megan Cushing, who married him in 2012. “I mean, it’s hard to believe, but off the field he’s not very -- he kind of keeps to himself, he’s not the most outgoing person. Once you get to know him, he can be wild.”

When she met him, they were both athletes at USC and one of Brian's teammates, Taylor Mays, kept teasing her about how Cushing had a crush on her. On their first date at a Mexican restaurant, he refused to eat anything but a piece of grilled chicken, completely unadorned.

She and their sons are part of the support system that helped him through the most difficult two years of his NFL career. Back-to-back serious left-knee injuries made him wonder whether he’d ever play again. It took him nearly two years to feel like himself again on and off the field.

“It was hell,” Brian Cushing said.

On Sunday, the Texans clinched their first AFC South championship since 2012. Saturday’s game against the Kansas City Chiefs will be Cushing’s first playoff game since the 2011 season. They’re here, in part, because Cushing finally feels like himself.

“I’ll tell you this, I’ve never seen a Mike linebacker play as hard as he plays,” Texans coach Bill O’Brien said. “He throws his body around, he hustles from sideline to sideline, he’s done a lot to put in time into the training room to get healthy, and he is definitely one of the leaders of our team.”

'Hard Knocks' adversaries, Brian Cushing and Alfred Blue are friends Alfred Blue and Brian Cushing know how to get the best out of each other and when to have a laugh. Ganguli

One of the darkest days was on Oct. 20, 2013. Cushing lay on the ground at Arrowhead Stadium staring up into the Missouri sky thinking it was over.

Chiefs running back Jamaal Charles' helmet had cracked Cushing's leg and torn a ligament; he had suffered a torn ACL on the same leg the year before. For a few dark moments, Cushing looked up and let himself sink.

“That’s it,” he told himself. “It sucks to go out that way, but that’s it. That’s what it was meant to be.”

It wasn’t the last time he would think that.

In a 2013 game against the Chiefs, Brian Cushing suffered a broken leg and torn lateral collateral ligament -- the second season in a row that was cut short by a serious injury. Jamie Squire/Getty Images

“There were days of real depression that I don’t think people know the guys that get injured go through,” Megan Cushing said.

Cushing was raised in New Jersey to expect greatness out of himself ever since his father, Frank, noticed his athletic ability during T-ball.

“It looks like you have a world of talent,” Frank Cushing told his son. “Other people would love to have it. Do something with it.”

Frank was so hard on him that others wondered how Brian, the youngest of his siblings, dealt with it.

Today, Brian Cushing speaks reverently and appreciatively of the way his father raised him. He feels he saw the fruits at each level of football when he became the “alpha” of each group.

“He would yell at me, and I would laugh and I’d smile,” Cushing said. “And he knew mentally I had the makeup to get through anything.”

Cushing felt that way, too, and sought challenges. He went to USC to feed his competitive fire and prove to himself he could play with anyone. He became a Texans first-round pick in 2009, then Associated Press Defensive Rookie of the Year.

The next few years tested his mental makeup.

In 2010, Cushing received a four-game suspension for a positive drug test. He and his family vehemently denied any wrongdoing. The Associated Press revoted on his rookie of the year award, and he won it again.

He played every game in 2011 but suffered a torn ACL in Week 5 of 2012 and a broken leg and torn lateral collateral ligament in Week 7 of 2013.

And when doctors gave him a timeline for his injuries, Brian immediately reset them.

“I kind of had unrealistic expectations,” he said. “… If they told me I was going to run in March, I thought I’d run in February. Just really tried to push myself. Sometimes it wasn’t the best for me mentally. I would get discouraged and get upset.”

He leaned on his wife and his parents for support. Even being with his son Cayden, who was born just after his torn ACL in 2012, helped.

“It was tough love I would give [Brian],” Megan Cushing said. “And sometimes he needed to be loved and told it was going to be OK, and I support whatever he wants to do. But there were times I would say you’ve gotta get through it. You’ve gotta be tough. Keep going. You have your family to support, but you have so much more to give. I know this sucks, but you can get through it and you will.”

The thought of playing again drove him, too.

Normally a team leader, Cushing had to simply lead himself. Learning how to walk, to jog, to run took time. He had to learn the difference between just being able to run and being able to play professional football. At the start of the 2014 season, he was technically healthy but clearly still recovering. The Texans managed his playing time and his responsibilities, another frustration for Cushing.

During 2015’s organized team activities (OTAs), suddenly something clicked. Everyone from his wife to his coaches to his teammates could see a difference. He still had three surgeries that offseason, but they were minor.

“To kind of get that whole feeling back and the whole, just general sense of where I am, it feels great,” Cushing said. “Makes me truly enjoy and love playing again.”

Back to being himself, Cushing had 110 tackles this season, his first 100-tackle season since 2011. He played in all 16 games, serving as the defense’s quarterback, calling plays in every package it has.

Being himself again meant being …

“Crazy,” said Bengals linebacker Rey Maualuga, his teammate in college. “A crazy white boy from Bergen Catholic. ... If someone blocked him in practice, he made sure that that person, whether they were a running back or a tight end, he made sure to -- he doesn’t care what the play was, he’ll go down and like try to knock them out.”

“It’s just a lot of crazy things,” Texans rookie linebacker Benardrick McKinney said. “He’s a funny guy. He’s a big, bad kid. He’s always up to something. When something is going on, blame Cush.”

“He was a tough guy,” Blue said. “A leader. A jokester. Somebody that just annoyed everybody, got on everybody’s nerves.”

“I love that craziness,” Texans nose tackle Vince Wilfork said. “He loves this game. You can win a lot of ballgames with guys like him.”

They laugh and roll their eyes, but none denies what he means to them.

“It’s an honor playing beside Cush,” McKinney said.

He’s not alone in feeling that way.