Is Norichika Aoki’s Baserunning Cause for Concern?

Mandatory Credit: Benny Sieu-USA TODAY Sports

When the Royals acquired Norichika Aoki, they acquired a player who could get on base at a high rate. Perhaps more importantly in the eyes of the Royals’ front office, they acquired a leadoff hitter with a lot of speed. In his two MLB seasons, Aoki has stolen 50 bases, and among qualified batters, only 13 players in all of baseball have more stolen bases since the start of 2012. Unlike those 13 players above him, however, Aoki has been rated as a below average baserunner (-3.4 BsR). How can a player who obviously has sufficient speed have such a negative impact on the basepaths?

Almost all of that negative value came from Aoki being caught stealing 12 times in his 32 attempts, for a success rate of just 62.5%. That’s not good. That’s barely better than speed demon Jeff Francoeur in his illustrious base-stealing career (59.8%). When a number like that shows up in a player’s profile, I always have to dig deeper to find out what else is going on.

In 2012, Aoki stole 30 bases and was caught stealing 8 times, which was a success rate of 78.9%. That makes more sense. Even though Aoki isn’t a young pup anymore, his speed shouldn’t have completely evaporated during his age 30 offseason. So the question remains: how did Aoki have such a brutal year on the bases? I decided to look at each of his CS instances to try and figure out what happened.

Here’s a link to Aoki’s game logs from 2013, with the games in which he was caught stealing at the top. To sum them up, he was caught stealing second base 7 times, he was picked off second 1 time, and he was caught stealing home 4 times. Of those 7 times he was caught stealing second, 3 times he was thrown out by Russell Martin, and once each by Welington Castillo, Humberto Quintero, Miguel Montero, and A.J. Pierzynski. Obviously you don’t like seeing a player cut down on the bases that many times, but it wasn’t like Aoki was thrown out by a bunch of scrubs. The league average CS% for 2013 was 28. Here are the CS% for each of those catchers:

Martin: 40%

Quintero: 36%

Montero: 33%

Pierzynski: 33%

Castillo: 29%

So every catcher who threw Aoki out at second was above average at throwing out would-be base stealers. Not much shame in that.

I wasn’t able to find all the details for the 4 times he was caught stealing home, but at least 1 was on a failed double steal attempt, and at least 1 came on a failed suicide squeeze play. Part of Aoki’s struggles come from him seeming to be too aggressive at times, but there is also something to be said for his coaching in Milwaukee. The Brewers had the second highest total of stolen base attempts in baseball (192), trailing only the Rangers in that department. However, their overall success rate was 74%, the 11th best rate in the majors. While that’s not terrible, it does show the team as a whole to be quite aggressive on the basepaths. Perhaps Aoki was given too bright of a green light, which may have done more harm than good.

It remains to be seen if the Royals’ coaching staff will be able to improve Aoki’s value as a baserunner. Coaches can only do so much with a player’s running instincts, but they should be able to rein in his aggressiveness a bit, and hopefully they can teach Aoki to pick his spots more wisely. The Royals weren’t exactly bashful on the basepaths, either, but they did have a much higher success rate, swiping bags on 82.7% of their attempts. I’m not suggesting the Royals have some kind of secret to guaranteed baserunning success, but there could be a chance Aoki returns to his previous performance levels as a runner. Or at least somewhere closer to an Aoki-2012-level than a Francoeur-career-level.

Even though more research quells some fears about his issues on the bases, Aoki is far from a lock to be another Jarrod Dyson in Kansas City, but it does seem like there may be a reasonable explanation for his dropoff in baserunning value from 2013, beyond him catching a case of Old Guy Syndrome. Much has been made about Aoki’s ability to get on base at the top of a lineup, and that is a very valuable asset to have. There is no doubt that he has speed, but for several reasons, some listed above, Aoki hurt his team with his baserunning last season. To increase the kind of positive impact Aoki can have on the Royals, he’ll need to significantly improve in that department next year.