If you’ve spent any time thinking about Michael Pineda, you’ve probably spent some time trying to figure out what’s wrong with Michael Pineda. He strikes out a ton of guys, walks very few, and posts FIPs better than league average. He also gives up a lot of home runs, has trouble with runners on base, and can’t seem to keep his ERA anywhere near league average.

Pineda’s season debut yesterday against Tampa Bay appeared only to offer more of the same. Despite recording a strikeout-to-walk ratio of 6:0 against 18 batters, Pineda ultimately allowed four runs in just 3.2 innings (box). While one game isn’t going to tell us much, yesterday’s performance didn’t do anything to suggest that this year’s version of Pineda is going to differ much from last year’s.

We didn’t always write articles trying to figure out what was wrong with Michael Pineda. Back in 2014, when Pineda was just returning from a series of injuries that kept him out for most of three seasons, Jeff Sullivan praised Pineda for his aggressiveness and improved command despite a somewhat lengthy layoff. The following spring, Eno Sarris examined what appeared to be a nasty changeup that could serve him well. Jeff Sullivan followed up a month later to discuss the possibility that Pineda was benefiting from increased velocity while also managing to locate his fastball and change in the right spots. That piece was written right after Pineda struck out 16 Baltimore Orioles without yielding a walk. For the rest of the season, Pineda put up an okay 3.92 FIP and a bad 5.02 ERA, which he essentially duplicated last in 2016.

So last season, Eno took a look at Pineda, writing two pieces in one day. The first highlighted Pineda’s command, which maybe was inferior to what Pineda had exhibited previously. The second noted Pineda’s problems with runners on base, which could have been a product of pitching from the stretch. Sarris also hypothesized that Pineda might be too afraid of conceding walks with runners on. Finally, this past offseason, Nick Stellini stepped up, noting that Pineda had tended to throw a lot of fastballs in the middle of the zone (which got hit really hard) and many of his sliders out of the zone (which were balls). On their own, both Eno’s and Nick’s ideas have merits. Let’s combine their hypotheses and see what happens.

Let’s begin by looking at fastball command. The graph below shows Michael Pineda’s fastball location from 2016 — against righthanders, in both cases — with bases empty and runners on base. (Images courtesy Baseball Savant.)

So what do we learn here? With the bases empty (on the left), Pineda throws a ton of fastballs right down the middle. With men on (right), he still throws it down the middle a decent amount, but also heads to the corner some. This lends some credence to Nick’s theory that Pineda is merely throwing too many dang fastballs in the middle of the plate — as well as Eno’s on-base/stretch theory, as Pineda appears to behave differently (whether on purpose or not) with runners on. In both cases, he gets smashed equivalently conceding a slugging percentage in the high .500s.

Now let’s check on the slider.

With the bases empty (left), Pineda throws a bunch of sliders down and out of the zone. With runners on, though, he gets a lot more of the plate. As for results, with the bases empty, players slugged just .283 against the pitch. With runners on, that number jumped nearly 100 points to .378. And while we’re dealing with only 100 or so plate appearances in each instance, the heat maps tend to support the difference.

Whether a product of approach or simply an inability to command pitches, Pineda definitely does something different with runners on base. Last season, pitchers lost about two percentage points in strikeout rate with runners on base compared to bases empty. Pineda, however, produced roughly the same figure. Pitchers added 1.5 points when it came to walk rate, but Pineda dropped his rate by a percentage point. For home runs, pitchers see a big drop with runners on base, from 1.26 HR/9 to 1.05. There’s some logic in that: if walks are going up and homers are going down, it suggests pitchers are being more careful. Pineda’s walks go down, though, and his homers increase from 1.13 per nine to 1.76.

Some of Pineda’s home-run rate is due to pitching in Yankee stadium, but when he gets on the road, his results are almost as bad; he sees a big spike in doubles to make up a bunch of the runs he loses by allowing fewer homers. It’s not purely an exit-velocity issue either. He didn’t see great results in exit velocity against last year, but he wasn’t all the way at the bottom either. It certainly seems like the two major culprits are an excess of fat fastballs and an alteration to his approach with runners on base.

We won’t get into the approach with runners on base from yesterday’s game because we only have nine right-handed batters faced — although he did give up five singles in those plate appearances appearances — but we can take a look at location, generally, of both the fastball and the slider. Here are Pineda’s fastballs and their results, per Baseball Savant.

I count 16 pitches here that are clearly in the strike zone. Of those, six turned into hits, with three called strikes, three fouls, two whiffs, and two outs in play. That isn’t what you want to see. The upper portion of the zone saw more called and swinging strikes, but it also saw the home run. As for the slider, it looked pretty good.

That’s a lot of swinging strikes, fouls, and outs here — and most of them are in the bottom of the zone. Pineda threw only three changeups (two for balls), but all three were pretty well located. In the end, Pineda got six strikeouts without allowing a walk, but he also gave up a homer and five runs. His one-game FIP is 3.17 and his one-game ERA is 9.82. Those numbers represent extremes for Pineda, but they are essentially an exaggerated version of what we’ve seen the last couple years: a lot of strikeouts, few walks, a lot of homers, and a lot of runs.

I don’t know that we’re any closer to figuring out Michael Pineda, but it certainly seems as if he’d be better served by locating his fastball towards the top of the strike zone more consistently. He could also take some steps with runners on base, either by attempting to be more careful with the heart of the zone or by working in a way that more closely resembled his windup (and perhaps abandoning some control of the running game in the process). Those things might help, but we don’t know for sure if they’re even possible. He’s a free agent at the end of the season, so maybe he will just get traded to Pittsburgh at some point and let Ray Searage figure it out. Until then, he’ll remain a mystery.