Toughness has a limit.

For football players, that’s a harsh reality to accept.

It’s even harder for players whose games are built on a tenacious, hardened mentality.

Perhaps no Badger embodies that mindset better than senior safety Jay Valai, who plays with a massive chip on his shoulder and has gained a reputation as one of the league’s hardest hitters.

But Valai encountered that very limitation against Purdue, where he struggled with an injury early in the first half and was replaced by backup Shelton Johnson.

Valai partially tore his right calf muscle during the bye week and he couldn’t walk. The senior’s status had improved by game day, and while defensive backs coach Chris Ash allowed him to start the game, it became apparent that Valai wasn’t himself.

The senior captain wanted to tough out the injury and continue playing, but Ash made the switch.

“I wanted to be out there bad, especially with this being my last year,” Valai said. “But it was a smart move, because if I can’t go out there full speed, as much as I want to be out there, I don’t want to be a detriment to my team.”

But at halftime, with UW down four, Valai had some work done in the training room, showed better mobility and convinced Ash to let him play.

“He spent most of the first half getting stretched and getting loose. After halftime he moved around pretty good so I said OK, I’ll give you a shot,” Ash said. “He was out there at full speed so we stuck with him.”

Toughness may have a limit, but you can bet Valai is going to test it.

It’s part of who he is. It’s part of what’s made the 5-foot-9 inch safety so successful.

Now the calf injury is just the latest one for Valai here in 2010. In fact, the trips to the training room began way back in fall camp.

“It just started in camp when I tore my PCL and injuries have kept coming since,” Valai said, who later suffered a rib injury that forced him to miss the entire Minnesota game. “If I got to play through it I have to play through it. It’s getting better. The knee is getting better and I don’t really feel the ribs anymore, so it’s been better.”

Playing through injuries is always a complicated subject for even the toughest players.

Valai is widely respected as one of the senior captains, but his teammates know he needs to be healthy to be effective. That goes for everyone on the roster.

“Jay believes in himself and he believes that he can play through injuries with that football mentality,” free safety Aaron Henry said. “I just tell him if he can’t go, don’t try to go out there and put us in a bad situation because you’re injured.”

Problem is, Valai wants so desperately to be out there. He understands he needs to step aside if he’s injured for the good of the team, but that doesn’t make it any easier.

Like the rest of the seniors, this is it for Valai. With each passing week his collegiate career gets one step closer to its inevitable end. And unfortunately for Valai, his final season hasn’t gone according to plan.

Many believed this would be the year Valai established himself as an impact safety on a consistent basis. Entering 2010, Valai had been a two-time, second team All-Big Ten selection by the coaches and personal expectations were understandably high.

This was going to be the year Valai went from just being a big-time hitter to becoming a top-notch all around safety. A defensive back who could make plays on the ball and be presence in the run game.

At this point, Valai has just 28 tackles. He has yet to record an interception or force a fumble. The injuries have been frustrating and at times debilitating, but Valai’s role in this defense has changed.

The highlight reel hits are not his priority. His job is to limit big plays and make sure he tackles.

Still, Valai set the bar high this season and he worked all offseason to reach that level.

“The year is not going how he wanted it to go, but obviously that could turn around at any point,” senior cornerback Niles Brinkley said.

He has three games left, plus a bowl game, to fight through the injuries and end his Badger career on a high note.

But this season isn’t about proving to the world he’s tough; Valai is now trying to prove he’s a winner.

“I’m trying to be a tough guy too often. But I want to play and I have a lot of passion to play,” Valai said. “I just need to do my job and do what it takes to win… whatever it takes.”