CLEARWATER, Fla. -- For every baseball player who ever lived, there has been a spring like this, a year like this.

You look up and you're about to turn 36, not 26. Your body aches in places it has never ached before. Your contract is a year from its expiration date, and no one has made a move to extend it. The numbers on your ESPN player card look so odd, you’d be half-tempted to suspect they were typed in there by some devious hacker in the middle of the night.

This is baseball. This is life. Even when you’ve gotten used to being The Indestructible Man.

Even when you’re Roy Halladay.

Maybe he’s about to win the Comeback Player of the Year award. Maybe he’s about to stagger through another year in which his back hurts, his shoulder barks and his fastball forgets to hop the way it used to.

But this is it, a defining year in his Hall of Fame career. And he’s well-aware of all that’s at stake.

No matter how early he rolls into the ballpark parking lot, no matter how methodically he’s worked with the Philadelphia Phillies’ medical and training staff to redesign his delivery, his workout program and his throwing program, he has no idea what’s ahead.

And on Wednesday, the first day of a pivotal spring training, he had no trouble admitting that.

“I think any player would honestly tell you, 'You never know,'” Halladay said, on Day 1 of his fourth (and possibly final) spring training with the Phillies. “Every year, you come into spring training, and you come in hoping that you’re going to feel good and you’ll be able to pick up where you left off. But there’s no guarantees. … I know that. And I’ve known that my whole career.”

It’s now 13 years since a funny thing happened to Roy Halladay on his cruise to stardom: He turned himself into such a mechanical mess, he wound up all the way back in the Florida State League. That was 2000. He hasn’t taken anything for granted since.

“I got my wake-up call a long time ago,” he said Wednesday. “So I know it’s always a battle to try and stay ahead of the curve.”

But even he never saw his 2012 nightmare coming. He’d come to believe that if he worked hard enough, prepared long enough and ran far enough, he could withstand all those pitches, all those innings, all those extra miles on his odometer.

And he couldn’t have been more wrong.

So now, after a season in which his ERA nearly doubled (from 2.35 to 4.49), in which he spent a month and a half on the disabled list, in which his moments of once-standard brilliance were few and far between, he has blown up the blueprint and started over.

You know those predawn runs through the Clearwater blackness? That’s a wrap. He’s an intervals runner now, not a half-marathoner.

“I think those 4 a.m. runs, for him, might be done,” said his spring workout partner, Kyle Kendrick.

Halladay also has tweaked his delivery to take the strain off his back and shoulder. He’s blown up his longtime workout program and substituted a whole new regimen. And he’s convinced he has found answers to questions he had trouble solving all last season.

“I feel good all the way around,” he said. “I’m not here to predict anything, but if I can feel the way I feel right now and maintain it and get stronger through the course of spring training like I normally do, I feel very confident that I can get back to [where he was].”

Where he was, of course, was at a place that almost no one else of his generation has occupied. A place where he won Cy Youngs in each league, racked up five top-three Cy Young finishes and threw 220 innings or more eight times in a span of 10 seasons.

And with the way he did it, the look in his eye as he did it, he constructed an aura of indestructibility around himself that seemed like something out of 1969, not 2009.

“It was something,” said his manager, Charlie Manuel. “It was absolutely unreal. But he’s thrown a lot of bullets, man. When you stop and think about it, he’s thrown a lot of bullets.”

So now, will all those bullets add up to the beginning of the end for this man? We’re about to find out.

Just not yet.

For what it’s worth, Halladay was the first Phillies pitcher to take the mound this spring, grunting through a turbo-driven bullpen session at 8:30 Wednesday morning, with GM Ruben Amaro Jr. and eight members of the major league and minor league coaching staff looking on intently.

But the plan is to ease him into the spring, with shorter outings early on and a gradual buildup as they go along. So it won’t be until late in the spring, Manuel said, that any of them will know, really know, whether the old Doc Halladay is back.

Make no mistake, though. They can’t wait to start finding out -- because two key things are riding on it: (A) their season and (B) Halladay’s future. That’s all.

The Phillies’ only ticket to October is built around their aces -- Halladay, Cliff Lee and Cole Hamels. And they need all three of them, the manager admitted. But there are more doubts swirling around Halladay than the other two combined. So no wonder all those eyeballs were focused on him Wednesday morning.

“He doesn’t have to throw no-hitters and things like that,” Manuel said. “But he’s got to pitch something similar to what he used to. And I think he will.”

The manager is talking about Halladay, Lee and Hamels combining for “50 to 60 wins.” Which comes to 17 to 20 apiece, if you’re calculating along at home. Just for the record, no National League team in this millennium has had three 17-game winners (or better) on the same staff. But for the 2013 Phillies, that’s not just the mission. It might be a necessity.

Meanwhile, if Doc Halladay wins 17 to 20, he would be setting himself up for an enjoyable journey into free agency next winter -- except for one thing:

He said Wednesday he doesn’t particularly want to journey into free agency.

“I really don’t,” he said Wednesday. “I think if I had my druthers, I would be here until I’m done. And as good as they’ve been to me, I think they realize I’d be as good to them as I could be. So going forward, I really don’t see myself playing anywhere else. And I don’t want to play anywhere else.”

Of course, a year ago this time, neither did the Phillies. But then came last season, when both sides decided to stop thinking about Halladay’s next contract until they could figure out what he’d be at the end of this contract.

And the end of this contract is now just eight months away. So the time has come for The Ace to define exactly what he is and prove exactly what he can be. Again.

This is baseball. This is life. Even when you’re Roy Halladay.