One of the most controversial scouting practices is the use of The Good Face. Ken Funck once wrote about The Good Face in these very pages: 

For decades, many baseball scouts have claimed the mystical ability to identify certain characteristics desirable in a young player by merely studying their facial features. The sabermetrically inclined, especially those outside the industry, have been known to scoff at this claim as just another discredited belief to which "baseball men" cling in a vain attempt to protect their oracular role in an organization. Not only was it impossible to quantify The Good Face, scouts didn't even seem able to agree on a standard definition, throwing around generic terms like "strength," "virility," "maturity," "determination," and "square-jawed confidence." The most unintentionally revealing description comes, perhaps not surprisingly, from Al Campanis: "I never used to sign a boy unless I could look in his face and see what I wanted to see: drive, determination, maturity, whatever." Huh? See what you wanted to see? Any description that ends with the word "whatever" is by definition both subjective and nebulous. Yet baseball men insisted that they could provide an accurate, objective measurement – but unlike stopwatches or radar guns (famously disdained by the old-timey), the only instrument that could measure The Good Face was available to just a select few: the eye of a veteran baseball scout.

Now comes word out of London that The Good Face might just be real. More block quotes: 

However, new research suggests that the shape of a man’s face can indicate whether he is likely to be a good sportsman.

The study, carried out at Goldsmiths, University of London, found that Japanese baseball players with short, broad faces are more likely to display acumen on the sports field. 

It is believed the explanation could be that having a wider jaw is an indication of having high levels of the hormone testosterone and that this plays a part in determining physical strength and aggression. 

This isn't the first time that science has found a link between face and athletic performance. A study of NFL starting quarterbacks, for instance, found that every single one of them had a much more symmetrical face (a common proxy for handsomeness) than the general population. There's a cause/effect problem there, as it could be that handsome athletes are chosen to lead their teams at an early age; or that teammates prefer to be led by handsome athletes, whether or not those handsome athletes throw the ball farther. But regardless, that study also suggests that The Good Face could be real. Funck, in that piece linked above, suggested The Good Face might correlate to a different approach at the plate.

Now that The Good Face has been validated by science, let's scout some faces. All faces are from a Wiki Commons search for "face." 

Face 1:

Scouting report: Right-handed pitcher with three-quarters release and plus fastball in the mid-90s. Secondaries slow to develop, durability an issue, max-effort. Long face. Not enough Good Face to start, but has the stuff, if not yet the control, for late-innings relief work. Probably went to Coachella back when it was still pretty small, relatively speaking, and you didn't have to sell your car to buy tickets. 

Face 2

Scouting report: Lightning-quick hands, good power for his size, could hit 25+ home runs at highest level. Doesn't have the arm for the left side of the infield, but should stick at second base. Future hitting instructor. Good observer. Probably rides his bike to the ballpark. Good Face. Good Tan Face. 

Face 3

Scouting reports, from left to right: 1. Good Face, solid hit tool, plus power, but could be a base clogger. 2. Good face, left-handed reliever, plus slider, deceptive. 3. Good face, no. 2 starter, big durable body. 4. Bad face, pinch-hitter.

Face 4 

Scouting report: Bad face. Too passive at the plate, will be exploited in higher levels. Nice guy, good teammate, lousy player. 

Conclusion: It's worth pointing out that a lot of published scientific findings can't be replicated. Interesting findings, like this one, get published and picked up by news outlets, like this one, before they've stood the test of replication. One last block quote

For some years now, scientists have gotten increasingly worried about replication failures. … C. Glenn Begley, who spent a decade in charge of global cancer research at the biotech giant Amgen, recently dispatched 100 Amgen scientists to replicate 53 landmark experiments in cancer—the kind of experiments that lead pharmaceutical companies to sink millions of dollars to turn the results into a drug. In March Begley published the results: They failed to replicate 47 of them.

So while it's interesting that there might be reason to believe in The Good Face, it's likely to remain controversial for some time still.