Very recently, Lorenzo Cain started for the American League in the All Star Game. He was entirely deserving of the honor and was not merely a product of the Royals’ impressive get-out-the-vote campaign. Cain entered the break with a 140 wRC+ in 322 PA, putting him 23rd among qualified hitters between two gentlemen named Jose Bautista and Joc Pederson. Cain’s offense alone would get most players into the Midsummer Classic, but it certainly helped that he’s been a superlative defensive outfielder and had 4.0 WAR at the end of the first half.

The best center fielder in baseball is Mike Trout. That’s not opinion or analysis, it’s a fact. It might as well be one of the laws of physics. Any debate on the matter is manufactured for shock value. Andrew McCutchen has a very strong case for the next spot on the list. It’s probably not bulletproof, but it’s difficult to refute. After McCutchen, the waters get a bit murkier, but Lorenzo Cain is a strong candidate for number three.

He’s been a four-win player in half a season, and if you extrapolate his season to 650 PA, he’s an 8.1-WAR player. If you’re more responsible and use a combination of ZiPS and Steamer, he’s tracking toward 6.0 WAR. Anyway you slice it, Cain is playing like one of the best players in baseball at this moment in time and he’s doing it with defensive numbers very much in line with his career norm.

He’s seventh among positions players in WAR this year. He’s sixth over the last calendar year. He’s 15th over the last two calendar years. Over the last three calendar years, he’s 21st in WAR among position players, despite being roughly 400 to 600 PA behind most of the players ahead of him on the list. Cain’s success isn’t a flash in the pan occurrence.

Cain’s defense was been great from the beginning. He’s been a quality base runner for almost his entire career. No one’s questioned his speed or defense in years and the line always seemed to be between role player and starter, contingent on the development of his bat. Cain’s evolution from solid to great has been about the 24 square feet on the third-base side of home plate. If he could put together an average profile at the plate, he was looking at a nice major-league career. But he had an 80 wRC+ in 2013 and it looked like he was headed for an inflection point season as the Royals geared up for a critical year in 2014.

Last year, Cain post a 111 wRC+ in 502 PA. The concern going forward was that it was buoyed by a .380 BABIP and held down by a 4.8 BB% and 21.4 K%. His ISO in 2014 was .110. There’s no wrong way to play gold-glove defense with an above-average bat, but a .380 BABIP served as a warning sign. You can post a .380 BABIP for a season, but doing it year after year is exceptionally difficult even if you’re a speedy line drive machine. Cain’s BABIP was probably going to come down and if he wanted to follow up his 4.9 WAR 2014 with another great one, he was going to need to find another trick at the plate. Cain arrived last year, but no one was convinced he had truly established himself a star.

You’ll have a job in the majors if you can play a +15-run center field, but you won’t necessarily be an impact player if your bat isn’t at least pushing league average. Cain had two potential ways to improve after 2014. He could cultivate his discipline, therefore offsetting BABIP regression with a higher number of balls in play, or he could start making those balls in play count more by getting them to travel farther. He could take the discipline route or the power route. He cleverly chose a way to achieve both.

Cain’s best offensive season prior to 2015 was 11% above league average. This year, he’s been 40% better. That’s the kind of jump that is hard for a dispassionate observer to ever totally believe. The interesting thing is that Cain’s BABIP has fallen from 2014 to 2015 from .380 to .364, and while BABIP isn’t the only kind of regression, it’s usually the one associated with massive swings in performance. Rather than riding some batted-ball luck to his 29% offensive increase, Cain has improved his contact rate and power simultaneously.

The difference between “Lorenzo Cain: Quality Major Leaguer” and “Lorenzo Cain: Guy on MVP Ballots” comes down to how much you believe in the offensive gains. The results are the results and you can’t argue that he has been better, but the two components most worthy of exploration are his out of zone contact rate and his isolated power.

In 2014, using the PITCHf/x strike zone, Cain’s contact rate on pitches outside the zone was 54.6%. It hadn’t been above 60% since his partial season with the Brewers many years ago. In 2015, it’s 70.4%. That’s a massive jump, accounting for roughly 36 balls in play that would otherwise have been swinging strikes in 2014. That could be a dozen extra hits already, depending on how you want to apply BABIP to out-of-zone pitches. The specifics aren’t terribly important, but the overall direction is. Instead of swinging and missing at pitches out of the zone, Cain is hitting them into the field of play.

Now, an astute observer might recognize that making contact with a pitch outside the zone might be worse than swinging through it if it is leading to weak contact that’s ending the plate appearance. That’s true in theory, but it doesn’t seem to be the case in practice for Cain, considering the ISO jump from .110 to .175 and the 10-point jump in hard-hit batted balls. His walk rate has come back to his career norm, so while that’s helped, it’s really about fewer strikeouts and more power.

In thinking about power, there are really two ways to get better. You can either hit the ball more squarely on average, or you can hit the average ball with more force. Cain seems like an easy study because you generally don’t see a lot of players getting physically stronger between 28 and 29. We’re usually thinking about players in their early twenties when talking about guys who start hitting the ball harder. It seems like Cain is among those players making better contact rather than harder contact. There’s obviously no way to be sure, but it’s a defensible hypothesis in context. Cain is striking out less and he’s hitting for extra bases more often. It seems like he’s barreling up the ball more effectively.

Specifically, Cain has closed a hole in his swing. That’s really what this comes down to. Cain probably isn’t a true talent 140 wRC+ hitter, but there is a very real reason to believe he is a better hitter than the one we saw a year ago. Observe two simple heatmaps, plotting Cain’s contact rate in 2014 and 2015:

There are lots of little improvements to notice everywhere, but the bottom third of the strike zone is the focus. Pitchers used to be able to get ahead of Cain and then put him away with a pitch down in the zone. Comparing minute swing differences is often a hunt for confirmation bias, but the difference could be a mechanical tweak that allows Cain to get the bat to the ball more effectively or it could be the product of a better prepared hitter. Cain had a very exploitable weakness and now he doesn’t. Instead of swinging through so many pitches, he’s hitting them and hitting them hard. Is that surely predictive of future success? It’s hard to say.

For the first half of the year, it’s worked very well. It might be a fluke and pitchers might find a counter to Cain’s new move, but Cain with a 17% strikeout rate and an above-average ISO is a very dangerous player, even as his BABIP settles into a more reasonable place in the months ahead.

Cain has two more arbitration seasons before he hits free agency, when he’ll be entering his age-32 season. He didn’t play baseball until he was an upperclassman in high school and it took him until he was 28 to have his first big year in the majors, so he’s a little behind his peers in terms of cashing in on his success. The age element likely means that Cain’s decline will come just as he’s hitting his stride, but we probably also don’t know how aging curves affect players with Cain’s unique history.

It’s probably safe to say Cain is better than the Cain we knew from 2010 to 2014, but he’s also probably not going to be one of the best two-dozen hitters in the game going forward either. In studying his trajectory, a very interesting comparable player emerges, however. The age is all wrong and the handedness is backwards, but Lorenzo Cain and Jason Heyward have been very similar players lately (stats since the start of 2013).

Name PA AVG OBP SLG wRC+ BsR Off Def WAR Lorenzo Cain 1266 0.288 0.337 0.410 108 9.5 20 45.4 11.6 Jason Heyward 1425 0.266 0.345 0.405 112 5.5 25 30.8 10.7

It’s a fascinating comparison that is both depressing and encouraging for Heyward watchers. On one hand, Heyward has only been Lorenzo Cain when Heyward was supposed to be a great player. On the other hand, Lorenzo Cain blossomed into a great player in his late twenties, and Heyward still has those years ahead of him.

Cain’s glove is reason enough to tune into a Royals game, but this first-half power spike has really changed the conversation. It’s not unheard of for players to luck into three good months of power, but Cain seems like a good “this is real” candidate because you can tie it to making more contact low in the zone, and the fact that he’s still pretty far behind his peers when it comes to hours spent in a batter’s box, making an improvement like this more plausible.

At 29, he’s not a novice, but it does make some sense that a player might continue to develop later into his career if he didn’t play the game his entire life. Particularly if the growth is mental and he’s becoming more adept at pitch recognition, for instance.

It’s been a tremendous run for Cain and the Royals. Without Alex Gordon for an extended period, Cain’s ability to maintain his first-half surge will be critical to their success. You don’t normally bet on a player to sustain a 30% increase in their year over year offensive performance, but given the circumstance surrounding Cain, his odds seem better than average. He’ll never be Mike Trout or Andrew McCutchen, but the 2014 version of Cain with a little more power is still one of the better players in the game.