If there's a trend in baseball other than hitters looking to get smarter about putting the ball in the air, it just might be that outfielders are playing deeper. We saw it work well for William Fowler last year, and we're seeing Adam Jonestry the same thing this year. We saw Andrew McCutchen try to do the opposite last year, only to have it backfire terribly, and now, with his return to center, he's reversed course. Major League center fielders averaged 312 feet from home in 2015, and so far in '17, they've moved a full five feet deeper.
But no trend is one-size-fits-all, and no one goes against the grain on just about everything like Billy Hamilton. He's the fastest outfielder in baseball; you already knew that, but we showed it in data with our new Statcast™ "Sprint Speed" metric. Since Hamilton has little power in his bat, he's one of the hitters who shouldn't be trying to elevate. And in a world where deeper is cooler, he is playing shallower. Much shallower.
Through Wednesday, there were 40 players who had played center field for at least 500 pitches. No one is playing as shallow as Hamilton is, averaging just 297 feet from home plate. And what's more, it's not even really close. He's a full seven feet shallower than the second-shallowest fielder, Jacob May of the White Sox. Hamilton is more than 30 (!) feet shallower than Michael Trout, Rajai Davis and Carlos Gomez.

Now if this were simply the way Hamilton always approached things, this wouldn't be much of a story. But that's not really the case, because last year, Hamilton averaged 311 feet from home, deeper than 18 other center fielders. That means that no one's taken a bigger step in than he has.
Biggest reductions in center-field depth in 2016-17
-14 feet -- Hamilton, Reds
-9 feet -- Jake Marisnick, Astros
-7 feet -- Adam Eaton, Nationals
-7 feet -- Andrew Romine, Tigers
-6 feet -- Fowler, Cardinals
(minimum 500 pitches on field in both years, all data through Wednesday's games)
Some of those changes have some obvious reasons behind them. The Astros, for example, removed "Tal's Hill" and brought in the depth of their center-field wall more than 20 feet, which explains Marisnick moving in. Eaton and Fowler each left Chicago for new teams, new ballparks and new defensive strategies. Romine merely went from exceptionally deep (332 feet) to very deep (324 feet).
None of that applies to Hamilton, though, who is in the same park with the same team as he's been since his 2013 debut. Reds third-base coach Billy Hatcher, who manages the team's outfield positioning, offered some possible explanations when he was asked by MLB.com's Mark Sheldon this week.
"It's the teams that we're playing against," said Hatcher. "It will vary depending on the ballpark, too. We'll be getting a little wind here. If it's blowing out, we'll play him in a little bit more, because the ball is going to go out regardless. It just depends on the day."
Gif: Billy Hamilton 2016-17 outfield depth
It certainly makes sense to adjust strategies based on what the situation of the day calls for, and it's true that Hamilton has played more shallow so far this year in nine games at home (294 feet) than in five games in St. Louis and Pittsburgh (303 feet). Then again, four of those home games came against the powerful Brewers, who have baseball's highest average distance on non-ground balls in play this year, in addition to leading the sport with 29 homers. Two more, entering Thursday's game, have come against the Orioles, who led the Majors last year with 253 homers. If it's an opponent-based strategy, these are unusual opponents to employ it against.
The wind, too, doesn't seem like a large factor. For only one game so far in Cincinnati this year -- April 6 against the Phillies -- was the wind at first pitch reported as blowing out. It could be that the Reds, so far, have rated highly as a ground-ball-inducing staff, pushing Hamilton to believe he'll get more batted balls in front of him. It could be that it's the third week of the season and that this will even out over time.
Or it might just be that Hamilton's game-changing speed just makes him feel comfortable that he can still get to balls hit well over his head that most center fielders wouldn't be able to get to. In the past two weeks, we've seen him do this twice, first to make a difficult play on McCutchen look easy:

And then to rob Nick Franklin on a ball hit straight over his head:

The question remains, though, whether all this is necessary. Unlike Fowler, Jones and McCutchen, all the metrics already loved Hamilton. By the Statcast™ metric Catch Probability, he was baseball's best center fielder in 2016. Defensive Runs Saved thought he was the third-best center fielder, even though he was at the disadvantage of missing the final month of the year due to injury. It's not like there was a ton to fix here.
Hatcher added, correctly, "Billy is one of the best outfielders in baseball," and also suggested that Hamilton is largely free to make his own choices. "I don't mess with him too much about playing. Sometimes if he gets too shallow, I will move him back a little bit. He knows what he's doing."
It's difficult to argue with that. Shallow or deep, there's no one who can track them down quite like Hamilton.