So far this season Justin Morneau has seemed as comfortable facing lefties as Mitt Romney would as the opening act for a Phish concert.

In spite of performing quite well against right-handed pitchers (hitting .310/.386/.561 and smacking 8 of his 10 home runs), among qualified hitters Morneau's .100 average off of left-handed pitching (8-for-80 as of Wednesday) is the lowest in baseball. This is not simply a fluky situation; the Twins first baseman is completely lost mechanically at the plate against his left-handed brethren.

Prior to the nasty concussion in 2010 Morneau had handled lefties decent enough over his career. Dating back to 2004, he had hit lefties at a .269/.319/.468 clip. However, since the knee to the head in Toronto, he has posted a .124/.167/.200 line against southpaws. Perhaps it is simply rust, an injury or maybe something psychologically about being in the batter's box and a 90 mile per hour plus fastball that cross in front of your head. Maybe it is a combination of all three. Either way, whatever is responsible for this decline does not seem like an easy fix.

Lending credence to the notion that it may be more rust or psychological rather than a physical ailment like his wrist or shoulder is the amount of times he is fool by sliders from left-handers now versus two years ago. According to pitch f/x data, in 2010, left-handed opponents threw him sliders 21% of the time. Morneau elected to swing at 53% of those thrown his way while whiffing at 14%. This year, opposing team's have had their lefties increase the number of sliders (31%) in response to Morneau's inability to layoff of the breaking pitch as he has swung at 70% of all left-handed sliders thrown his way while whiffing at 26% of them.

This statistical breakdown leads one to believe that Morneau is struggling with pitch recognition out of the pitcher's hand. To make matters worse, his mechanics – particularly against left-handed pitching – has become so abysmal that he's unable to keep himself locked in on pitches when teams attack him on the outer-half of the plate.

His batted ball distribution chart paints a disconcerting portrait of how far his skills against left-handers have eroded.

Back in 2010 Morneau was much better at using the entire field. As same-sided hurlers would throw sliders and fastballs on the outer half of the strike zone, he would be able to deposit them all over the field. Now, as we have seen more recently this year, Morneau is having difficulty doing anything against lefties besides yanking the ball:

This is particularly ineffective when the majority of pitches to him are being thrown away.

As noted above, Morneau is mechanically out of whack as well when it comes to swinging against lefties. Focus on his front side (hip) and compare his swing from 2010 (top) versus one from this past June against the Phillies' Antonio Bastardo (bottom):

You will notice that in his 2010 stance and mechanics, Morneau kept his feet closer together and made a long stride at the ball. Once he began his swing, he demonstrated the ability to keep his hip on the ball and open up along with his swing as his hands come to the ball. These traits were consistent throughout many of his clips that season.

In the more recent version however, he had widen his stance thereby shortening his stride (perhaps in efforts to reduce the movement and improve contact). When he swings, his front side basically splays wide open well before his hands come through the hitting zone. Because his front side has already committed to opening up, Morneau has no choice but to pull the ball – even if it is located on the outer-half of the plate. This too, unfortunately, is a trait that also carries with him throughout many of his swing clips from this year and is not unique just to this match-up.

With his issues at the plate continuing to progress, it became apparent that in the past week or so Morneau and hitting coach Joe Vavra have made some changes to his approach to combat this slide. The most notable of which is removing his leg kick altogether. Instead of the prominent leg lift and stride as seen in the clips above, Morneau is now simply lifting the heel of his front foot while keeping his toes firmly in the dirt:

Additionally, there seems to be more concentration on keeping his weight back and going the other way with the pitch (at least you can see this in the clip against Bruce Chen and the Royals or today with Darin Downs on the mound for the Tigers).

The rationale behind this alteration seems to be focused on making contact by keeping him from drifting out with his front side. By not having a stride, Morneau's hips will have less of a tendency to open up. Likewise, by minimizing the movement it allows him to keep his head still and in theory see the ball better. Of course, at the same time, this significantly reduces his power potential and it may be the reason why during Thursday's game, Morneau went back to his original stride (with little success):

In addition to the season long woes against lefties, Morneau's power has been MIA since June 4 when he hit his last home run. The ball just is not coming off of his bat the way it had previously. According to BaseballHeatMaps.com, before June 4 Morneau's fly balls and line drives were travelling an average of 298.27 feet. Since then, that average has dropped to 259.89 and has resulted in five extra base hits in 101 plate appearances since his last home run.

Given that he has made some changes, this indicates that he is not wholly comfortable at the plate. While he and Vavra are attempting to get back on course, it raises the larger question on whether he should continue to be used regularly against left-handed pitchers. With Morneau inserted in the fifth spot against southpaws and having him continue to produce at the abysmal rate that he has greatly diminishes the effectiveness of the lineup.

The Twins have three games remaining before the All Star Break and in two of those they will be facing southpaws. This should be a good time to sit the first baseman out for a few games, giving him some added rest and time to concoct a game plan against lefties.

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