There’s an old saying among Dominican ballplayers: “You can’t walk your way off the island.” The implication is that you have to hit — and swing — to get noticed by Major League Baseball talent evaluators and have the chance to leave the country for greater glory.

Of course, we all know that the modes of evaluating baseball players have changed, rather radically, over the past decade or so. A greater importance has been given to some statistics and skills, while others have been devalued. Plate discipline is probably chief among the physical aptitudes that have been played up, and the prevailing wisdom has become that pitch recognition isn’t a choice or approach — it’s an inherent skill of its own.

In fact, plate discipline is now generally viewed much the same as the freakish physical ability to throw a 100-mph fastball. You either have that ability or you don’t, and no amount of practice is going to develop that skill.

But going back to international baseball players, if the saying holds true for Dominican players, it would seem to be doubly true for Cubans. Recent history seems to bear this out.

Before going any further, it bears mentioning that this is a generalization — Sabermetrics, after all, is based on aggregates — and won’t always hold true on a case-by-case basis. But for the current Cuban players in MLB who have shown good plate discipline (Yasmani Grandal, Kendrys Morales) there are far more (Yoenis Cespedes, Yuniesky Betancourt, Alexi Ramirez, Yunel Escobar) who have shown a characteristic penchant to hack.

Which brings us to Yasiel Puig‘s incredible start to his young career.

Unfortunately, stats do not seem to be available from the Cuban National Series, so we can’t measure Puig’s aggressiveness based on stats alone before 2012. However, a scouting report from early in his American career says Puig “still showed a propensity to chase bad pitches now and then, and usually in bunches.” To contradict that report, however, Puig’s walk rate in the minors wasn’t awful, at about one in every ten plate appearances.

However, since arriving in Los Angeles, Puig has hacked, hacked again and hacked some more.

Granted that Puig’s propensity to swing at anything and everything has worked out for him so far. However, it’s not just that Puig swings so often that is worrisome, but specifically which pitches he’s swinging at. In short, Puig is swinging at an enormous number of strikes out of the zone, and there is no way such an approach can be successful long-term.

Remember Jeff Francoeur? If you don’t, you should, he was only waived by the Kansas City Royals just last week. In any case, Francoeur’s career arc should serve as a warning to anyone putting too much stock in Puig’s meteoric rise.

Francoeur was not just a highly touted player coming up through the Braves’ system, his pure athletic gifts earned him the nickname “The Natural,” and he graced the cover of Sports Illustrated during his rookie season in Atlanta. More to the point, his numbers during his first 32 games in the big leagues are eerily similar to Puig’s. In fact, they’re even better.

Francoeur’s slash line (batting average/slugging percentage/OPS) during that first month of his 2005 campaign was .370/.739/1.125. Puig, by comparison, is currently at .409/.677/1.114. But both players have one caveat within their auspicious beginnings that, for Francoeur, ended up derailing a promising career.

During Francoeur’s first 122 plate appearances, he never walked. Not once. Puig, likewise, has taken just five free passes (one intentional) in 135 trips to the plate.

But more than just the total amount of walks that each player did (or rather didn’t) take, is the specific kinds of pitches they’re swinging at. As of Monday, Puig’s O-swing rate (the percentage of pitches outside the strike zone he swings at) stands at 41.1 percent. Likewise, his Z-swing rate (pitches inside the strike zone) is 82.3 percent, for an overall swing rate of 56.2 percent. By comparison, Francoeur was at 34.9/83.1/60.9 during his rookie season.

Suffice to say, this does not bode well for Puig, as plate discipline tends to be the strongest indicator of future performance among players without much of a body of work at the professional level.

As some have pointed out, though, Puig’s ability to drive the ball to the opposite field may offset some of his aggressive tendencies. However, again taking Francoeur’s career as a template, it just doesn’t follow that hitting to all fields makes up for hacking at pitches outside the strike zone (or in the strike zone, for that matter) with such frequency.

Thanks to some statistical heavy lifting by Andrew Shen of Beyond the Box Score, the spray charts of each player bear this out.

Photo via BrooksBaseball.net

As you can see in the chart above, Puig has done a very good job of hitting to all fields, and there’s no doubt that’s helped him be so successful. However, as Francoeur’s spray chart likewise shows, the ability to hit to all fields isn’t necessarily the best predictor of success.

As Shen points out, spray chart statistics through Brooks Baseball aren’t available before 2007, so that doesn’t include Francoeur’s rookie season. However, this is actually a better way of showing that spray charts don’t necessarily portend overall performance. Francoeur’s OPS during the years this spray chart counts is a lowly .716, but pulling the ball too often clearly wasn’t a problem for him.

Of course, these aren’t the only factors that indicate Puig is playing over his head. Anyone who understands basic Sabermetrics knows that a .494 BABIP flatly isn’t sustainable.

However, saying that Puig is due for a decline isn’t going out on a limb — of course he’s not going to slug .667 over his entire career. However, the eery similarities to Francoeur should be a warning sign that Puig isn’t just due for a decline, but there’s a distinct chance he could end up flaming out in spectacular fashion.

Well, everything Puig has done so far has been pretty spectacular, so all we can do it wait and see.