The realization hit defensive tackle Mike Newkirk early one morning recently.

Yes, Newkirk knows he's a senior, heading into his last season at the University of Wisconsin.

Even though he has been unable to take part in spring football practices lately, following shoulder surgery, he already has spent considerable time thinking about maximizing every second of his final year.

But it wasn't until awaking one morning, when it fully hit him, how a lifetime devoted to football could potentially be over after this season.

Newkirk hopes to get a chance to play in the NFL, but he knows there are no guarantees.

"Doing this your whole life, it's like, what do I do after this?" Newkirk said last week. "I woke up the other day, I knew it was my last year, but the other day it kind of hit me.

"I almost had like a panic attack. That's why you've got to try to do everything you can — and hopefully you won't be done playing after this year."

Newkirk always has been a maximum-effort player in everything he does. So, that has put him in something of a quandary.

How does somebody who has devoted himself to giving every last ounce of energy to playing football find a way to give a little more? That's the question that consumes him these days.

"It makes you want to make sure you step back and appreciate everything," Newkirk said. "Even those workouts. That's something that gets lost a lot of time, in between the injuries, the surgeries, the gassers, everybody's tired and it becomes kind of a grind. Guys lose sight that this is a privilege. There are a lot of guys that would give anything they have to be able to come back and do this.

"I don't want it to end. Just make sure you appreciate everything and realize, there's going to be some day, I'm going to be sitting at home on my couch, I'd give anything to be able to go back and run some gassers and be dog tired. You kind of learn to make that feeling your friend."

So far, Newkirk's career with the Badgers could be classified as solid, not spectacular. He was good enough to start five games as a redshirt freshman in 2005 and has gotten markedly better each year.

He was part of a three-man rotation at defensive tackle in 2006, along with Jason Chapman and Nick Hayden. Newkirk had one of his best games in the win over Arkansas in the Capital One Bowl, with five tackles, including one for loss.

He seemed poised for a breakout season last year, before senior defensive end Jamal Cooper was kicked off the team before the first game. Newkirk was forced to move to left end, where he started the first 10 games. He moved back to left tackle for the final three games after Chapman suffered a torn ACL.

Despite playing out of position, Newkirk eventually turned himself into a dependable player outside. He finished the season with 41 total tackles. His 10� tackles for loss ranked second on the team. But it wasn't enough for him.

"That's one thing, sometimes, I've been disappointed in," Newkirk said. "For me, it never really seems like I've done anything yet. I've always expected myself to be exceptional. It's like I've never really had that standout year yet.

"I've progressively gotten better and I've been solid. Some people would say, `You got moved (to end) last year.' I don't really worry about all the details. It doesn't matter where I'm at. You think about all the work you put in, now's the time for it to pay off. I've got to do whatever I can to make sure that happens."

The shoulder surgery was a minor arthroscopic procedure. Newkirk was injured last season and it didn't get better in the offseason. It flared up again during spring practice, so he figured it was time to get it fixed.

Newkirk originally was supposed to be out six weeks, but now expects it to be only four. He should be fully cleared in May and have a full month before summer conditioning starts.

In the meantime, he has thrown all the energy he would normally put into practice into everything else, from watching DVDs to lifting weights.

"What you did yesterday can't be good enough for today," he said. "You've always got to find a way to keep improving. As you get closer and closer to the top and the more and more things you do, that gets harder and harder, because the amount that's left gets smaller and smaller. You've really got to become fanatical in every little thing — sleep, food, nutrition, the things a lot of guys don't think about."

Newkirk's not the only one feeling that way, which is good news for the Badgers. He's part of a large senior class that wants to make up for the disappointment of going 9-4 last season.

"There's a lot of different ways it can help," Newkirk said of the seniors. "You're not going through it alone. The guys next to you have that same feeling.

"Then you'll be able to look across and know, if it's someone who really cares about the game, cares about the program, somebody you've played with, there isn't that question, `Is he giving everything he's got?' You'll be able to look over there and know."