Red Sox Shortstop Xander Bogaerts Is Fulfilling His Potential

Despite the 2015 season being all but done, the Boston Red Sox have a lot to be happy about. They seem to have the future of the outfield settled as well as some questions in the rotation answered. Ian York takes a look at Red Sox shortstop Xander Bogaerts and his impressive season.

Last year, at the age of 21, Xander Bogaerts put up a .240/.297/.362 line in 144 major-league games. While not completely awful, those numbers are far from good, especially considering the high hopes Sox fans had for Bogaerts. This year, though, Bogaerts’ numbers have been much more in line with initial expectations. His .323/.353/.426 line puts him behind only Troy Tulowitzki, Brandon Crawford and Jung-Ho Kang among major-league shortstops, and he is in second place for batting average among all qualified players in the American League.

His success this year has not come from any dramatic changes in his approach. He is really doing more or less what he did last year, but more consistently. Looking at his numbers as rolling 10-game averages highlights this:

The dots show Bogaerts’ rolling ten-game averages, the red line is his season average to date, and the dashed green line is the baseball-wide average for each statistic. Aside from a slow start to the season that was offset with a short hot streak in June, he has been a model of consistency throughout the season.

Last year, Bogaerts handled fastballs reasonably well and with some power:

These charts (which are from the umpire’s viewpoint, so that the right-handed batter would be standing to the left of each) show the distribution of pitches thrown to him as the green contours in the background. The grey polygon indicates the de facto strike zone that umpires called in 2014. The sizes of the outer white circles represent the number of called strikes within each of the grid squares, and the sizes of the inner circles represent the number hits, while the color of the inner circles represents power: grey is the MLB average number of bases per hit (about 1.5), with red and blue representing more or fewer bases per hit, respectively.

A very rough rule of thumb is that a decent batter has about 1 hit per ten strikes. In 2014 Bogaerts was just under that for the various types of fastballs, but he was hitting them with more than average power. However, he had much more trouble with breaking pitches, especially from right-handers, not hitting them for either average or power.

This year, he is seeing about the same mix of pitch types:

But unlike last year, he shows no weaknesses. He is able to hit just about everything, in just about every part of the strike zone:

Again, consistency is Bogaerts’ hallmark this year. He has – probably deliberately sacrificed a little power in order to make contact, as can be seen from the lower amount of red in this year’s maps, but the tradeoff has let him become one of the best-hitting shortstops in baseball at the age of 22.

His age is important, because on average offensive numbers increase dramatically between the ages of 22 and a player’s peak, power increases the most. A 22-year-old player on average has about 85% of his peak SLG values. If Bogaerts follows that trend (and he may not; there is huge variability between players) that would give him about a .492 SLG at his peak about the same as, for example, Adrian Beltre or Buster Posey this year.

Ian York has written about Koji Uehara, an impressive start by Eduardo Rodriguez, Joe Kelly’s approach in certain counts, the effect of better bullpens on offensive strategy, Rick Porcello’s resurgenceMatt Barnes’ first start, the much improved Jackie Bradley, Jr., and Wade Davis.

Follow Ian on Twitter @iayork.

Check out Tom Wright’s elimination article about the Arizona Diamondbacks.