Max Kepler's early power surge might not last

For anyone who pays attention to the world of top Minor League prospects, the language used to describe players becomes familiar quickly. ‘The bat is good enough to play anywhere.’ ‘He may have to move off shortstop.’ ‘He’s looked overmatched at times, too much swing-and-miss.’ These are phrases that sometimes toe the line of cliche but are actually useful in conveying what scouts are seeing.

When Minnesota Twins outfielder Max Kepler first started to appear on top prospect lists the phrase that stuck out to me was ‘he’s going to need the doubles to turn into home runs.’ That’s to say that the hit tool is strong, but the game power is a question mark. Not the worst thing to have said about you; after all, doubles are still a desirable outcome.

Those scouting reports are why it's so surprising to see that Max Kepler already has 10 home runs in the majors this year, and he needed just 189 plate appearances. The remarkable thing is not that he has shown a lot of power, but it’s that he’s done it so quickly, as it's said that power is the last tool to develop. The 23-year-old has already matched his single-season high, which he accomplished in rookie ball for the Elizabethton Twins of the Appalachian League in 2012.

Last year in 515 plate appearances across three levels (High-A, Double-A, and three games in the big leagues), Kepler totaled only nine home runs. To say that Kepler would currently be on pace for 30 home runs if given a full season of plate appearances is true, but obviously the randomness of baseball means we can’t presume that this is where his true talent level lies now. Let’s take a glimpse at the quality and characteristics of his home runs.

First we’ll take a visual look at where his home runs have landed, thanks to Baseball Savant. Not all of these home runs were hit at Target Field, but that is the park overlay since it is his home stadium.

Baseball Savant

So, eight of his 10 home runs were pulled to right field. That’s fine, no problem there. Pretty common as most home runs are hit to the pull side, and as you can see Max Kepler pulls the ball 8 percentage points more than the rest of the league while hitting 5.4 percentage points more fly balls.

The significant 6.4 percentage point difference between Kepler’s HR/FB rate and the league average is perhaps the most intriguing because, as shown by Russell Carleton, HR/FB stabilizes around 50 fly balls for hitters. Kepler has hit 54, which means there is a little bit of signal in the noise, though we should still expect some regression. The stabilization point is not a magic sample size threshold beyond which everything is significant. Let’s now take a look at the characteristics of his home runs thanks to the data collected by Statcast.

The predictably above average exit velocities are not surprising. You need to hit the ball hard to hit it out of the park. The slowest-hit home run was also the shortest, but the launch angle was perfect (as Dr. Alan Nathan has shown). What sticks out the most is that Kepler’s is the only ball with these characteristics (91 MPH at a 26° launch angle) to have left a ballpark this year. Similar batted balls have only a .105 batting average. The short right field porch at Yankee Stadium probably deserves a little credit for that one.

Of his 10 home runs, four of them have below a .300 average on similar batted balls. This means that depending on park, elevation, and weather conditions these balls are most often caught for fly ball outs. On the other hand, five of his home runs have an average higher than .700, so more often than not those batted balls do become hits. Even though the typical averages of his batted ball types vary greatly, it sticks out that seven of Kepler’s 10 home runs have an expected HR percentage below 12 percent. Certainly we are in the infancy of using Statcast data to analyze batted balls, but it’s safe to say that some of these were not 'no doubters'.

All of this is not intended to discredit Max Kepler and claim his power is a mirage. His home runs are not all wall scrapers, and it’s absolutely possible that he will develop 25-30 home run power in the future. It’s simply to say that his pace right now appears unsustainable. He has only 209 plate appearances in the bigs, and pitchers will find his weaknesses. Kepler has been successful so far at doing what the scouts had said he must, turn those doubles into home runs, but based on how he’s hitting them right now, some of them will probably turn back into doubles.

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Chris Anders is a writer at Beyond the Box Score. You can follow him on Twitter at @MrChrisAnders.