A very puzzling development for the Kansas City Royals in recent years has been the seemingly stunted growth of should-be-a-star 3B Mike Moustakas. Entire cottage industries are built out of fixing players, or increasing power, or pitch velocity, so it is no surprise there are no shortage of theories and criticisms of the young slugger. Truly the Royals seem flummoxed and have little to any idea as to why “Moose” is having such a rough time of it.
In reviewing the available video, Moustakas is presenting a pronounced back shoulder dip, almost a lean, as he follows through to the pitch. What would cause this? The tape showed something that is shocking in both its simplicity and its apparent lack of discovery.
When Moustakas swings, as he is about to make contact with the ball his right ankle rolls inward, (seen in the above file photo) causing a lack of balance and probably some discomfort which forces his body to reverse direction. This has the effect of Moustakas leaning away from the pitch as he is hitting it. Fangraphs confirms the theory — his best swings are against slower pitches that his affected bat speed can solidly connect with.
This problem also causes him to “pull-off” the ball as the reversal of direction looks to make his front shoulder fly out. The Royals thought they had accomplished progress by switching him to an exaggerated open stance, but this seems to have exacerbated the problem, actually putting more pressure on a presumably strong but muscle memory weak ankle.
In researching Moustakas’s history, I find an interesting tidbit about a devastating ankle injury that nearly ended the entirety of his athletic career while QB for Chatsworth HS football (California) in 2006. It is entirely possible, even probable, that Moustakas developed an involuntary turn in his ankle as he was healing at first due to pain.
However, when a quirk develops with muscle memory due to pain, the removal of that pain does not remove the habit. My prescription for Moose would be to adopt an upright position, the exact opposite of what the Royals have him utilize now, and a more closed stance. Moustakas has plenty of strength to get the head of the bat to the ball, and he needs to start practicing a clean front leg plant right away.
Royal fans should be happy that their young talent can still have a marvelous career with just a few changes allowing him to achieve balance and maximize his power. With some support and some changes, Moustakas may still lead many an October “Bull Moose Party” at Kaufmann Stadium.