What's wrong with Shin-Soo Choo?

It is no secret that after Shin-Soo Choo's strong seasons in 2009 and 2010 (.300 average, .397 OBP, at least 20 home runs, 85 RBIs and 20 steals), he has since underperformed. Although critics are often quick to bring up his injuries and off-the-field incident as a means to explain his dismal season in 2011, his lack of performance has continued into 2012, as he's hitting .240/.371/.344 with just one home run entering Saturday.

So, what is the problem with Choo? The answer may surprise you. First, take a look at a chart courtesy of "It's Pronounced Lajaway" writer Ryan McCrystal that showcases Choo's batting averages according to pitch speed.

Shin-Soo Choo BA by Pitch Speed

Choo's biggest problem has been sliders. During Choo’s impressive 2010 campaign he destroyed sliders, finishing with a .308 batting average against them with five home runs; however, since the end of 2010 Choo has managed a feeble .164 batting average against sliders. Choo has not hit a home run off of a slider since Oct. 1st, 2010.

If you are more of a visual learner, perhaps these two heat map interpretations can explain just how much Choo has regressed versus the dreaded slider. Check out the difference between the 2010 season and his at-bats since, and see if you can see the hole that has developed:

Pitchers have taken notice to this hole. Of the 10 games the Cleveland Indians have played against divisional opponents in 2012, nine featured Choo facing multiple sliders.

Although this is a big problem, it is not the only issue with Choo so far in 2012. You may have also noticed from the chart that Choo’s average versus pitches 85-plus mph has also declined in each of the past three seasons; however, the chart did not provide Choo’s splits versus right/left-handed pitchers. See below for the numbers.

Batting Average Splits

on Pitches 85+ MPH

Choo has managed to collect only two hits against left-handers this season on pitches of this type, the worst in the majors among players who have had at least 20 at-bats against 85-plus mph pitches. This may not seem like much of a problem considering it is more difficult for left-handed hitters to hit left-handers, but after seeing all of Choo’s success in past seasons versus left-handed fastballs it is alarming. It's a small sample size (Choo has 36 at-bats against left-handers all season), but worth watching to see if Choo continues to struggle in this regard.

A bright spot from this situation is the fact that despite Choo's significant struggles, the Indians find themselves at 18-14, leading the division by two games over the Detroit Tigers; however, no Cleveland fan should think that the team can have a successful season with a subpar Shin-Soo Choo.

Brenden Lowery writes for "It's Pronounced Lajaway", a blog that covers the Cleveland Indians. Follow Brenden on Twitter.