Before we get into the meat of this article, I feel like I need to preface everything, so that the message and significance aren’t unclear. You might find it dreadfully uninteresting to read through this brief preface, but then, just imagine how much better reading the article will feel afterward!

(1) This was originally titled “The Most Indiscriminate Swinger in the World” but then I thought better of that because you people are crude.

(2) This article makes use of PITCHf/x plate-discipline data, which some people might not find to their liking. It forces two bits of that data together in a haphazard ratio, which more people might not find to their liking. There are always going to be sample-size concerns, and especially in this instance. I am aware of how the analysis might be considered insufficient and yet I’m still comfortable with it, because it’s more right than it is wrong.

See, that wasn’t too bad. Off we go.

Anybody who’s spent much time on FanGraphs has spent time on the player pages and leaderboards, and is presumably familiar with the plate-discipline data made available. I remember how I felt when I first laid eyes upon O-Swing% and Z-Swing%. We had some ideas before, but now we had data. These days we have PITCHf/x data. Based on a certain PITCHf/x strike zone, we can record how many swings there are at strikes, and how many swings there are at balls. This is plate discipline. There’s a reason this stuff is given the plate-discipline header.

Undisciplined hitters tend to run high O-Swing% rates. Miguel Olivo runs high O-Swing% rates. You don’t really want your hitters to be swinging at pitches out of the strike zone very often. This can be partially off-set by high Z-Swing% rates. Not all strikes are hittable, but many strikes are hittable, and a called strike’s no good. In theory, a perfect hitter would have a well above-average Z-Swing%, and a considerably well below-average O-Swing%.

So the opposite of a theoretical perfect hitter would have a low Z-Swing% and a high O-Swing%. He’d watch a lot of strikes and swing at a lot of balls. This brings me to a guy named Pedro Ciriaco.

The versatile Red Sox infielder has opened some eyes by playing flashy defense and batting .316. Quality defensive infielders who bat .316 can be some of the most valuable players in the league. Ciriaco’s done it over a small sample of just 176 plate appearances, but followers of this year’s Red Sox have needed to squint to find positives, and Ciriaco’s been a positive so far.

But there are warning signs, and it doesn’t take a baseball genius to spot them. Ciriaco’s got three walks and 33 strikeouts to his name, which is just miserable. The difference between his OBP and his batting average is 12 points. If you’re on his FanGraphs player page, go ahead and scroll down. Ciriaco’s also swung at 46.4 percent of balls, and 59.4 percent of strikes. Something about that doesn’t seem right. Something about that seems incredibly wrong.

We have reliable PITCHf/x data stretching back to 2008. Since 2008, there have been 1,937 individual player seasons with at least 150 plate appearances. Out of all of those, Ciriaco’s O-Swing% currently ranks third-highest. His Z-Swing% currently ranks 1,349th-highest, in a tie. I decided to make up a ratio, with Z-Swing% divided by O-Swing%. This was mostly for curiosity, and it turns out that Ciriaco’s ratio of 1.28 is the lowest in the PITCHf/x era. Next-lowest belongs to 2010 Garret Anderson, at 1.32. Even if you think this ratio is mostly a load of crap, it’s not a good sign to have the lowest ratio in five years. It’s a ratio made up of two important statistics.

I decided to go over to Baseball Heat Maps to get a visual. Here’s Ciriaco’s swing heat map against right-handed pitchers, compared to the league average. I’m only looking at righties because Ciriaco’s sample against lefties is very small.

Swing-happy everywhere but over the middle of the plate. Over the middle of the plate is where the most hittable pitches get thrown. Not every hitter has identical hot and cold zones, and Ciriaco is a special snowflake, but that does not look to me like the swing map of a quality bat.

For added visuals, here’s a Ciriaco at-bat from Tuesday night. The at-bat lasted three pitches; I didn’t leave anything out.

Ciriaco took a first-pitch fastball for a strike, taking the whole time. He swung wildly at an 0-and-1 breaking ball in the dirt. He took an 0-and-2 fastball for a strike instead of protecting the plate. It isn’t at all fair to say that this is the typical Pedro Ciriaco at-bat, especially while he still owns that high batting average, but this was an at-bat that highlighted some weaknesses.

Pedro Ciriaco has generated good results, but his process has been miserable, and there’s no part of that batting average that looks sustainable given everything else. I probably don’t even need to mention that Ciriaco’s running a high rate of hits on balls in play. Pablo Sandoval makes over-aggressiveness work, and of course Vladimir Guerrero made over-aggressiveness work, but even their approaches were better than Ciriaco’s, and they made or make more contact. Ciriaco swings at the wrong pitches and he doesn’t have a lot of power.

For his career, spanning parts of three seasons, Ciriaco owns a big-league .775 OPS. Not bad. Actually quite good, for an infielder. That’s over 216 trips to the plate. Over 1,080 trips to the plate in triple-A, Ciriaco owns a .649 OPS. He’s got 23 walks and 172 strikeouts. If there were something special about Pedro Ciriaco, one figures it would’ve shown up in the minors, too. It didn’t. Ciriaco debuted in 2005, and last year Jose Bautista drew more walks than Ciriaco has drawn in his entire professional career.

What this turned into was a post critical of a versatile Red Sox infielder, and there probably aren’t too many people who thought Ciriaco would keep hitting anyway. But we’ve also managed to identify the hitter who’s had perhaps the very worst approach in the entire league. You might hate your favorite team’s hacker, but he’s had a better approach this year than Pedro Ciriaco has. Ciriaco, to date, has been one of the Red Sox’s few positives. Consider that and you see how badly things have gone wrong.