Tigermetrics – Pitchers in 2020

Normally, these reports are only available to those who have joined the Patreon family (which you are always welcome to do if you have not already). This offseason, though, they are available for the masses. The patrons already got a look at some advanced stats on the hitters just over a month ago. Here’s a little something on the pitchers in our final retrospective piece on the 2020 season.

All the pitchers on here threw a minimum of 50 innings, with one exception in order to give a fuller look at the relief corps as well. Three of these guys, in fact, split time between the rotation and the bullpen, hence their middling inning totals. Let’s have a look at what each category means, plus one stand-out (for better or worse) in each category.

The first and second columns (IP = Innings Pitched; ERA = Earned Run Average) are pretty self-explanatory. The next column, RA, is “Runs Allowed” which basically gives a picture of how many runs the pitcher gave up, on average, whether earned or not. When compared to the ERA column, naturally everyone’s number is higher. The smaller the gap, though, the less the errors affected the pitcher in question. The pitcher with the smallest gap is Joe Gunkel, whose 0.16 run gap represents an uptick of just 5%. On the other hand, Shintaro Fujinami‘s gap is 1.53 (38.1% higher), which indicates that the errors really got the better of him, and that in some ways, his ERA is a poor indicator of just how many runs plated while he was on the mound.

FIP (Field-Independent Pitching) and xFIP both aim to remove defense from evaluating the pitcher. This not only removes errors but also regular hits — the logic is that pitchers have little control over where the ball ends up after it leaves his hand. A ball that dropped for a hit against one defender would have been an out with a more capable fielder. A well-hit line drive that results in an out does not really indicate that the pitcher has won the battle — just that he got lucky. A dribbler that no fielder can reach in time also does not indicate that the pitcher failed — just that he got unlucky. Therefore, only three categories are counted because they are all presumably within the control of the pitcher: walks, strikeouts and home runs. (With xFIP, numbers aim to remove ballpark factors — a home run at Meiji Jingu would be a harmless out at Koshien, after all.) A lower FIP than ERA (namely Koyo Aoyagi and Fujinami) indicates perhaps the pitcher got a little unlucky, while a higher FIP than ERA (particularly Yuki Nishi and Takumi Akiyama) indicates that perhaps the pitcher got lucky, or served up an unusually high number of long balls.

RSAA (Runs Saved Above Average) indicates how high above or below league average pitchers are at preventing runs from scoring. This is a cumulative stat, meaning it is easier (in theory) for a starting pitcher to achieve a higher number. Nishi is top on the team and it’s not even close. Fujinami bookends the team rankings with an ugly -11.4 runs below the league average. The fact that eight of ten pitchers listed here are above average is a good sign, though.

WHIP (Walks + Hits per Inning Pitched) is quite a common metric, and obviously the lower the number, the better. Hanshin has two pitchers (Nishi and Akiyama) below 1.00, which is the golden standard, and two more (Suguru Iwazaki and Robert Suarez) who are just above that line. It is also worth noting that the biggest culprit on the list, Fujinami, had a WHIP of 1.12 (21 H 13 BB in 30.1 IP) after his call-up in late September. That’s a ton better than he was earlier in the year.

The next three categories (K:BB, K:9, BB:9) all belong to Akiyama. He has the best ratios in the first and third, despite the worst ratio in the middle one. Consider this: he threw fewer pitches per inning than any pitcher in the entire Central League! Fujinami was the golden man when it came to strikeouts per nine, while Onelki Garcia finished the bottom two in all three of these ratios. Only poor control from Fujinami (particularly in his first 40 innings of work) stopped him from a clean (dirty?) sweep.

Perhaps it makes sense that the guys who pounded the strike zone the most consistently were also generally the ones who gave up the most home runs per nine innings of work. Akiyama, Nishi, and Gunkel are all known for their control, but that also means they are leaving themselves more vulnerable to the long ball. On the other hand, the slightly wild and definitely unorthodox Aoyagi gave up the fewest round-trippers (0.3) per 9 innings of work.

The next categories (K%, BB%, K%-BB%) are quite similar to other ones, so I will move ahead to GB%, LD%, FB%, and IFFB%. It is here that we see if pitchers are ground-ball pitchers or fly-ball pitchers. Neither is better than the other — guys like Aoyagi and Gunkel rely on the infielders (risky in recent years) and a dirt infield that is both fast and inconsistent from inning to inning and depending on the weather. They both also have fairly high line-drive rates, which can obviously lead to a lot of extra-base hits against. Meanwhile, pitchers like Akiyama, Iwazaki, and Yuta Iwasada count on the outfielders to track down balls in the expansive Koshien outfield, plus benefit from the in-blowing winds beyond the right-field bleachers. Somehow, two of the import pitchers – Suarez and Garcia – induce a lot of infield fly balls.

Iwazaki and Nishi had low ERAs not only because they are good, but because they step things up when runners reach base against them. Their strand rates (LOB%), 84.6% and 81.9%, are highly impressive, and contrast starkly with Fujinami‘s 62.3%, which shows that he needs to crank things up a notch after guys reach base against him (which happened a lot via errors). Doing so will not only improve his numbers, but probably give his mates greater confidence in him, that he can cover their mistakes by getting out of innings cleanly.

A high BABIP (batting average on balls in play) can indicate one of two things: either you are getting hit hard more often than league average, or you just had less luck than the average pitcher. In general, a .300 BABIP against is considered normal. Akiyama (.234), Iwazaki (.242) and Nishi (.243) were below (better than) league average, but they are also masters of messing with hitters’ timing. On the other hand, Fujinami ranked worst on the team with 33% of balls in play ending up as hits.