Byron Buxton is off to the kind of start to the 2021 MLB season that has Fantasy Baseball players wondering if this could be the start of a superstar turn. The 27-year-old is hitting .432/.479/.977 with an AL-best six homers in just 12 games, and it finally looks like he's going to live up to his long-expected potential.

And, best of all, it doesn't look like a fluke, because Buxton is absolutely crushing the ball. In the past, we wouldn't really have been able to quantify that, but thanks to the advent of the Statcast system provided via MLB, which tracks the velocity, spin rate, movement and dozens of other factors of every ball thrown or hit in games, we can see just how much Buxton is crushing the ball, down to the tenth of a mile per hour. He went three for six with a homer and a double Wednesday, and here's what that looked like: 

Overall, Buxton is third in the majors in average batted ball exit velocity at 97.7 mph while ranking first in hard-hit rate (batted balls over 95 mph) and barrel rate (in short, barrels are balls that have an "ideal" launch angle and exit velocity and thus have a high probability of becoming a hit). Which is all to say, Buxton's hot start to the season hasn't just been the product of good luck. He's not hitting seeing-eye singles or wall scraping homers -- in fact, his average homer has traveled an eye-popping 427 feet. 

And yet, despite all of that, I still have Buxton ranked below Marcell Ozuna, just like I did at the start of the season. Buxton has moved up a bit -- he was 20th at outfield in Roto leagues for me coming into the season and he's 17th now -- but Ozuna hasn't really moved down at all despite hitting .206/.316/.250 with batted-ball metrics that don't suggest he's been particularly unlucky -- he has a .214 expected batting average and .344 expected slugging percentage based on how hard and where he has hit the ball so far. Just like Buxton's hot start hasn't necessarily been the result of good luck, Ozuna's slow start hasn't just been bad luck. So, why haven't I moved them yet?

I think this example highlights an important thing to remember when we're dealing with these advanced stats: They are measures of what has happened so far and much better ones than traditional stats in many ways. But they aren't fate.

At this point, most Fantasy players know not to put too much stock into some early-season numbers -- nobody is claiming Brandon Nimmo is going to challenge for a batting title despite hitting .395, because his .567 BABIP is obviously unsustainable. Batting average, ERA, wins, even runs and RBI are important to Fantasy, obviously, but they are subject to a lot of factors outside of the individual player's control. They are the result of a player's skill level put into action in a game, but they aren't necessarily reflective of a player's skill set. You can fluke your way to a high BABIP. 

But something like exit velocity? You can't fake that, right? If you hit a bunch of home runs because you're crushing the ball like Buxton is, that's real. And if you're crushing the ball but not getting good results, the assumption should be that the production will follow. Hitting the ball hard is a direct measure of a player's skill set being put into action in games, after all. 

What Buxton has done so far isn't a fluke. But it's important to remember that that old sports concept of the hot or cold streak still applies here. It doesn't mean Buxton has been lucky; it means he might just be hot right now, in the traditional sense. He's locked in. He's seeing the ball well. Whatever hoary sports cliche you want to use probably applies here. 

It should go without saying that Buxton (or Joey Wendle or J.D. Martinez, to pick two other hot starters from opposite ends of the Fantasy spectrum) won't be able to keep what he's done up. These stats measure skill much more accurately than what we've used in the past, but you need to remember that skill isn't static. A player may have a baseline level of skill, but the ability to put that skill into action in games fluctuates constantly for every player. For some players, like Mike Trout, those fluctuations tend to be pretty small -- it's what makes him the best hitter in baseball. For someone like Buxton, as his career shows, the swings can be pretty wild. 

Hitters are constantly making adjustments, pitchers are making adjustments to those adjustments, and hitters are then trying to make adjustments to those adjustments. Sometimes guys just get hot; sometimes they can't hit anything. Of course, it's important to identify those swings and try to figure out where legitimate changes in that baseline skill level may be happening, because that's when you want to buy or sell players before everyone else catches up.

And that may be what's happening with Buxton, to be clear. The talent has always been there, and he was in the top 7% of the league in 2020 in expected ISO -- that's part of why I was so high on him coming into the season. But there will be a slump at some point. It could happen today. And you can't even begin to truly get the measure of a player until we've seen both the good and the bad, and how they respond to both. 

So, go ahead and be excited about Buxton. Be disappointed with Ozuna. But don't overreact to what we've seen so far. It's a long season, we're barely one-tenth of the way through it. Your preseason expectations should still be your baseline -- though maybe everyone's preseason expectations were too low on Buxton, too.