Baseball players don't change.
Or rather, they do change but they change in predictable ways.
This is one of the bedrocks upon which baseball analysis is constructed. Predictive baseball analysis, anyway. If players weren't predictable, we should not bother with predicting anything at all.
But players are predictable, which is why we're not surprised to see the Yankees in first place and the Mariners in last place. We can predict, with a large degree of accuracy, what a group of players -- say, a group of 30 players -- will do over the course of 162 games.
On the other hand, I don't know if anyone's ever gotten rich trying to predict the performance of single players. It's fun to think about, and it seems a shame that Randy Newsom's scheme to sell shares in his future baseball career didn't work out. Well, except that investors would have lost everything, since he pitched only 9⅔ innings after attempting to sell those shares (an enterprise that was quashed by Organized Baseball).
Our tendency, when a player does something unexpected, is to attribute this event to randomness. "Why, that's just a statistical fluctuation! Happens all the time!"
Which is true. It does happen all the time. What's also true: Most players don't fundamentally change, except naturally. A great 23-year-old hitter will probably become a great 28-year-old hitter. A terrible 25-year-old pitcher will probably become a terrible 33-year-old pitcher. And so on.
But not always. Which is what makes baseball a lot more interesting than it would otherwise be.
I think it's safe to say Jose Bautista isn't a statistical fluctuation. Just a few weeks before his 29th birthday, Bautista made some adjustments and somewhat magically went from marginal major leaguer to superstar, just like that.
Bautista's transformation might be the most dramatic in major-league history, but
Consider Trevor Plouffe.
In 2004, the Minnesota Twins used their first-round draft pick on Plouffe. For six years, he did little to justify the Twins' faith: just enough to keep getting promoted, but not enough to make anyone think he would ever be a particularly useful major leaguer. His minor-league line through 2010: 254/310/391 ... and he wasn't getting better as he moved up the ladder.
Then, 2011. In which Plouffe, somewhat shockingly, batted 313/384/635 with 29 long hits in 51 triple-A games. His performance in the minors got him a lot of playing time in the majors, first in May and then after the All-Star break. He did show some power with the big club, but otherwise wasn't impressive at all.
Then, 2012. In which Plouffe opened the season on the bench and got off to a horrible start, batting .133 with one home run in his first 60 at-bats, through the middle of May. And since then?
Since then, Trevor Plouff has been rather unworldly. In his last 24 games, Plouffe has hit 13 home runs. Including a recent stretch in which he hit seven home runs in seven games.
Random statistical fluctuation? I don't think so. There are just too many numbers: first those 51 games in the minors last season, and now these last 24 games in the majors.
So what happened? As TwinCentric's Parker Hageman details (with video!), Plouffe changed his batting stance and his swing, and went from from being a ground-ball hitter to a fly-ball hitter.
Could anyone have predicted this?
Well, the Twins must have predicted something. Otherwise they wouldn't have drafted Plouffe in the first place, or stuck with him through all those seasons of minor-league mediocrity. But a lot of teams draft hitters who never really learn to hit, and a lot of teams do stick with them for years. Especially the first-round draft picks.
Which isn't to suggest the Twins just got lucky with Plouffe. The've got a pretty solid record of developing young hitters. But we, as outsiders, can't simply trust an organization to develop every first-round draft pick. One year ago, we were still in the position of assuming that Trevor Plouffe would never really develop. Because the great majority of players who haven't developed by their 25th birthday never really do.
That's a guideline, though, rather than a rule. And it's good to get an occasional reminder. With big-time power.