Over the last three seasons we have seen Aaron Hill go from a legitimate MVP candidate to a player who is merely keeping second base warm until Blue Jays prospect Brett Lawrie makes his debut.
So what happened to Aaron Hill?
We will use a combination of sabermetrics and data analytics to find out.
2009: 103 Runs, 36 HR, 108 RBI, 42 BB, 98 K’s, .286 AVG
What do sabermetrics tell us?
The statistic that is most often used to evaluate luck is Batting Average per Ball In Play (BABIP). This statistic simplifies whether the hitter hit the ball where the defense was not at an unusual pace over a period of time.
When you watch a hitter flair a blooper between fielders or deliver a grounder that finds a hole, he is considered to be lucky and his BABIP rises. On the other hand, if he belts three line drives directly into the glove of a fielder, he is unlucky and his BABIP goes down. In order to evaluate whether a player is lucky or not, we compare his BABIP over a longer duration to evaluate whether he is having more or less luck than usual.
Aaron Hill’s career BABIP is .288. In 2009, Hill’s BABIP was .288 on the button, which tells us that he had his usual amount of luck that season. Therefore, we cannot ignore or write off his sensational statistics as a matter of a lucky season.
In 2009, Hill played up to his capabilities.
What pitches did he hit?
During his memorable 2009 season, Hill had a healthy diet of fastballs (58 percent), sliders (16 percent), change-ups (11 percent) and curveballs (10 percent).
Hill was at his best against the fastball with a .322 average and 19 home runs. Hill did have some trouble with the fastball inside, hitting just .218 in 55 at-bats. The same could be said about fastballs on the outside part of the plate, (one home run in 94 at bats with a .234 average).
Hill’s glaring weakness was off-speed pitches, particularly sliders and curveballs. In 180 at bats, Hill hit just .200 against those pitches with a 1:10 extra base hit to hit ratio.
2010: 70 Runs, 26 HR, 68 RBI, 41 BB, 85 K’s, .205 AVG
What do sabermetrics tell us?
In 2010, Hill was downright unlucky. His BABIP declined by nearly 100 points from .288 to .196. Furthermore, his strikeout rate and home run rate were relatively steady, which suggests Hill was putting the ball in play as much last season as he did in his stellar 2009 campaign. The ball just didn’t drop for hits.
What pitches did he hit?
It appears that pitchers made the necessary adjustments to Hill’s hitting last season. Instead of firing fastballs, they turned to the pitches that Hill struggled against the previous season including sliders (18 percent) and splitters (11 percent).
Additionally, pitchers spotted their fastballs on the inside and outside parts of the strike zone with greater success. Hill hit just .143 in 28 at-bats against fastballs inside, compared to .133 in 75 at bats on pitches outside.
In 2010, Hill was at his worst against change-ups. In 50 at-bats, Hill managed just one home run, while hitting a horrid .120.
His weakest zone against change-ups was low and from the middle of the plate to the outside. Hill had just a measly single to show for 21 at bats against those pitches.
2011: 4 Runs, 0 HR, 8 RBI, 3 BB, 11 K’s, .233 AVG
What do sabermetrics tell us?
It looks like luck is no longer the issue for Hill. His BABIP has rebounded to a healthy .275, however, his power has been sapped and he’s striking out more often.
Over the last three seasons Hill’s slugging percentage, which identifies power, has declined from .499 to .394 to a lowly .283 this season.
In addition, his strikeout rate increased from 14 percent to 16 percent to 18 percent during that span. In other words, Hill is not putting ball in play as often and when he does, it is with less power.
What pitches did he hit?
Hurlers are firing in change-ups at an increased rate to Hill. The off-speed pitch makes up 13 percent of the pitches Hill has seen, and in 9 at bats, Hill has yet to get a hit.
Of the 31 change-ups that Hill is facing, nearly half of them have come low and towards the outside region of the plate. This tells us that pitchers have done their homework against Hill and are throwing him pitches he has yet to hit consistently.