PHOENIX -- Generally, when a guy like Josh Donaldson is ready to take the jump from borderline major leaguer to star, we're the last to know.

Donaldson's 2013 season turned him into an MVP candidate (he finished fourth) and put him on the short list of elite major league third basemen. But most of why it happened took place in 2012.

Let's rewind to the spring and summer of 2012: The Republican party was grudgingly throwing its lot in with Mitt Romney. The Miami Marlins, ever so briefly, fielded a team with a legitimate major league payroll. And Josh Donaldson, from April-June 2012, was posting an OPS shy of .400 for the Oakland A's, earning him a trip down to Triple-A Sacramento.

But that very time of struggle in Oakland also gave Donaldson access to something he'd never had before: visual breakdown of every one of his at-bats.

"It was just kind of a swing plane adjustment that I made," Donaldson told me in the Athletics' clubhouse Monday morning. "It came about from being able to see myself on video, really for the first time ever. So it was kind of realizing what I was doing wrong, and then looking at other players that are pretty good. It was the first time, on a regular basis, getting to see my swing."

The results were enormously beneficial to Donaldson. In 2011, he'd posted a .783 OPS for Sacramento. In 2012, after putting his ideas and changes into practice, his OPS at Sacramento jumped to an even 1.000. He hit nearly as many home runs at the same level in half the plate appearances, his walk rate jumped and his strikeout rate plummeted.

"In hitting, they have what is called a load process," Donaldson said. "And as I said earlier, I'm gaining a better understanding of my load process, which in turn is allowing me to see the ball better. Instead of the ball feeling like maybe it's jumping on me, I'm actually able to see it for a long amount of time. And the better you can see the ball, the more you're going to know to layoff this pitch, or hit that one."

Donaldson said it took about a month with his updated process for him to start seeing the results.

"I remember I hit a ball, a home run to centerfield late in a game," Donaldson said of that 2012 Sacramento summer. "Sacramento is very similar to Oakland -- ball doesn't really travel. And I felt like it was pretty easy. There wasn't a lot of effort, the way I'd normally swing. I started feeling that. It's one of these things where you're not going to feel great all the time. The adjustments I've made allow me to still, I believe, have success even when I'm not perfectly on time, all the time."

By the time he returned to the Athletics on Aug. 14, he knew he was close to a breakthrough. He received an opportunity to play third base when Brandon Inge got hurt, and he immediately capitalized. He collected a hit in his first game, a home run in his second and four hits in his fourth. He raised his overall numbers considerably, playing every day at third base. The guy with the sub-.400 OPS through June put up an .844 from Aug. 14 through the end of 2012.

His manager, Bob Melvin, realized then he had something special on his hands.

"I think it was at the end of '12, when Inge got hurt, and then he took over at third base again, and had the last month that he did, numbers-wise," Melvin told me Monday morning in the A's dugout. "Then he had the playoffs that he did. Coming into '13, he knew he was gonna be the every-day third baseman, and that it was his to lose. And that opportunity for him, he was gonna take advantage of it."

For his part, Donaldson thought he had figured something very significant out. So the end of his 2012 season, officially, didn't keep him from running right through the tape and continuing into the offseason. He headed to a friend's house in Modesto and spent every day for the next two weeks working to perfect his new swing after Oakland's playoff exit.

"I went to a buddy's house because I felt like, in 2012, I was right on the brink of -- any day now, if we continued to play, something good was really gonna happen," Donaldson said. "So I went, and for about two weeks, kept grinding, trying to get that feeling. He was throwing to me in the cage, and we were working off a tee. And then I went back, took a month and a half off, and got back to it."

When he did, Donaldson had the luxury of knowing he wouldn't need to play five positions, as he had for Sacramento in 2012. He'd be a third baseman only now.

Donaldson credits this with helping his 2013 success, though again, it is hard to imagine the A's giving him that chance if he hadn't put up such good offensive numbers in 2012.

"That definitely helped," Donaldson said. "I definitely think that it plays a role, just for the simple fact that whenever you're playing five positions, you have to do maintenance for all five. You can't just wing it. Oh, you're gonna play left today? Well, I haven't taken fly balls in a month. No, you have to be constantly on the grind for all those positions, which, in turn, is gonna take energy from you being able to work on your swing."

Melvin pointed out the particular challenge when one of those five positions is catcher, with a career to back up his words.

"Me personally? Well, that's all relative," Melvin said, drawing laughter from reporters. "I kind of had to catch, and make sure I didn't lose my glove, if you look at my offensive numbers. ... As far as catchers go, you look at backups, they tend to spend a little bit more time on the defensive end, spend a little more time with that."

Melvin did allow for the fact that, had Donaldson made it as a catcher, his hitting would have allowed him some greater leeway at the position.

"He's a guy that's actually an offensive guy, and has always been a hitter, a guy with power," Melvin said. "So again, it was more just the opportunity, and it didn't matter where it was for him. I think he's one of the better defensive third basemen in the league."

And yet, Melvin agreed with Donaldson that if he'd been employed as a multi-position guy, that 2013 breakout might not have happened.

"Oh, I think definitely having him at one spot was key for him," Melvin said. "So he could focus, each and every day -- we have great infield guys here, Mike Gallego and Chip Hale, that worked with him, Phil Garner at spring training -- so it was the experienced guys working with him, and knowing he was going to be at one position, and the opportunity for him to play regularly was paramount to his success."

After his fantastic 2013, Donaldson repeated his 2012 postseason regimen, heading back to Modesto, taking the same time off, and looking to formalize the process that gave him so much first-time success, relatively late in his career.

His primary concern in spring training this year is trying to make his numbers with no one on base approach his superior numbers with runners in scoring position. It's a far better problem to have than the reverse, particularly for someone the A's are relying on to drive in runs. And often such discrepancies are one-year statistical noise. But Donaldson believes he had a different approach last year when guys were on base, perhaps due to how seriously his metaphor for clutch spots makes it clear he takes them.

"I would think it's one of those fight-or-flight mentalities," Donaldson said of clutch situations. "If you're about to die, you're going to focus more. If we've got runners in scoring position, I'm going to focus more, because there's an end goal. If I can drive him, that's my goal. If no one's on base, you're just trying to get on base, or maybe just do too much damage, instead of just allowing yourself to hit a single or double."

It's striking that someone sent to Triple-A with a sub-.400 OPS in the middle of 2012 is now, less than two years later, left to work primarily on hitting more like himself. But it's probably a lot less surprising to the guy who, back in the middle of 2012, had already figured out how he'd get here.