Albert Pujols became known as "The Machine" because he spent the first decade of his career thoroughly dominating Major League Baseball and putting up numbers that were so consistently elite, he was like, well, a machine.
While it's fair and accurate to point out that Pujols' decline began before he bolted as a free agent after the 2011 season, the gradient has gone from gradual to trap-door-like over the past two years.
After all, this is a hitter whose average season with the Cardinals was .328/.420/.617 with 40 homers, 41 doubles and an OPS+ of 170. In his first two years with the Halos, though, those same statistics look like this: .275/.338/.485 with 24 homers, 34 doubles and an OPS+ of 130.
Why have Pujols' stats been slipping? Surely, some of this decline is related to his advancing age—he turned 34 on January 16—as well as the fact that 2012 was his first season with a new team and in a new league, so some transition traps likely were at play.
Beyond that, though, Pujols' underlying skills have fallen off, too. As impressive as his mainstream numbers were for 10 years, he was also was known for having a stellar eye. But over the past five years, he's been enduring an icky combination of an increasing strikeout rate, a decreasing walk rate and worsening plate discipline.
Let's start with those first two.
Whereas Pujols' walk rate increased every single season from 2001 through 2009—that's incredible, by the way—it's dropped off regularly since that point, as the table shows. His last three seasons represent the three worst of his career.
Similarly, his strikeout rates three of the last four years have been his worst since his rookie season mark of 13.8 percent.
To be clear, Pujols' performance in these areas is still above average, but the trend—for him—is clear.
Here's where the rest of the plate-discipline story over the past five years—his contact and swing rates—gets told:
|* = % of pitches swung at outside the strike zone|
Again, the trend is easy to spot, right? Pujols has been making contact less frequently while also swinging more often overall, especially at pitches outside the strike zone—perhaps the most alarming aspect of all this.
So the problems have been identified, but what's the reason behind them?
Well, Pujols' second season with the Angels was wrecked by injuries to his lower half, starting with right knee surgery last offseason, which was followed by a partially torn plantar fascia in his left foot during midsummer. That foot problem has become chronic.
As such, Pujols spent much of the 2013 season playing well below 100 percent.
Need proof? Here's Pujols' account of his left-foot pain, as told to Bob Nightengale of USA Today—all the way back in early April 2013:
[Pujols] also can't forecast the severity of pain in his left foot, plantar fasciitis, which has never bothered him so badly this early in a season.
Pujols, who had arthroscopic surgery on his right knee during the winter, believes the surgery might have created stress on his left foot.
"Usually, it bothers me the most late in a season,'' Pujols said, "but this year it started early in spring training. I'm surprised. It's never bothered me this early in a season.
"It's never hurt this early in a season, not like this.''
In fact, Pujols told Alden Gonzalez of MLB.com last August that he had been playing at 45 percent for months. That estimate came about a week after a July 26 incident in which Pujols—his left foot already severely ailing by that point—suffered a tear in his plantar fascia, the connective tissue in the arch of his left foot.
That game actually proved to be his last. After using a walking boot and taking a couple of weeks to rest, Pujols finally was shut down for good in the middle of August, as Mike DiGiovanna of the Los Angeles Times wrote.
That's the primary reason the longtime first baseman wound up playing nearly twice as many games as the designated hitter (65 to 34).
The good news? Pujols made it clear last November—three-and-a-half months after the tear—that his left foot was more or less as good as new, per Gonzalez.
"Last year … it was a really tough year for me physically, in terms of recovering," Pujols said. "But now I feel really good, really excellent. With the foot, I feel 99.9 percent healthy."
If that's true, there's a chance Pujols can regain some of his superstardom, even at this late stage in his career. To do so, though, he will have to be able to rely on his lower half—especially his right knee and left foot—to allow him to do what he once excelled at: driving the ball, particularly the other way.
In general, there seems to be a little bit of a bad-luck factor at play in some respects. For instance, Pujols' power over the past two seasons has been impacted negatively by his HR/FB rate—that is, the percentage his fly balls that go over the fence—which dropped to 14 percent in 2012 and 11 percent last year, both of which are his lowest ever.
By comparison, Pujols' career HR/FB rate is 18.7 percent, and until 2012, at least 15.8 percent of his flies have been homers every single season of his career, many of which were better than 20 percent.
Then there's the more opposite field power. Take a look at Pujols' noticeable drop-off in slugging percentage from two different periods, 2009-2011 compared to 2012-2013, via Brooks Baseball's customizable heat maps of Pujols' hitting zone (recreated here in table form):
It's immediately obvious that Pujols' ability to drive anything from the middle of the plate and out, as well as middle of the plate and up, was dramatically reduced over the past two seasons.
No doubt that had something to do with his knee and/or foot injuries, as strength and balance from the lower half is paramount when hitting the ball the other way.
It's fair to wonder whether Pujols can "relearn" how to bash balls to the opposite field again after two seasons struggling to do so. Even more so when he'll also have other aspects of his offensive game to address—namely, cutting back on that nasty habit of chasing pitches out of the strike zone.
Then again, if a healthy Pujols really is a machine, he probably has the software needed for the reboot.
Statistics from FanGraphs were used for this story.
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