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Why the Pacific League is stronger

Swallows players celebrate capturing NPB’s interleague “championship.”

By Jim Allen

At the conclusion of this year’s interleague play on Thursday, the Pacific League’s cumulative record against the Central League 1,040 to 920 since interleague was created in 2005 as a part of the settlement of Japan’s only players strike so far.

For a long time, most of us simply assumed the leagues were relatively even in terms of quality. But the lack of CL championships in the Japan Series and the typically one-sided interleague results suggests that in some way that the PL simply has more talent. I was pretty slow to accept this until Yakult Swallows pitcher Shohei Tateyama answered my question about why the PL did so well by saying, “Don’t you think it’s because they’re just better than we are?”



Looking at NPB interleague games from 2009 to 2017 played in NPB’S 12 main parks, Tateyama’s observation appears to be correct. The first thing everyone seems to point to is the pitching.

In February 2006, then-Nippon Ham Fighters manager Trey Hillman said it was tough for the PL teams because few PL pitchers threw really hard. Other than Australian Brad Thomas, Hillman said, his hardest thrower at the time was a pitcher who probably would be in Double-A in the U.S. (Yu Darvish), and that his hitters were not used to the velocity of the hard-throwing CL pitchers.

A year ago, Alex Ramirez said the opposite, that the PL pitchers–particularly the relievers–throw harder, and that makes it harder for the CL hitters to adjust. This appears to be the case at the moment. According to analysis site Delta Graphs PL fastballs are 0.6 KPH faster on average than the CL heaters, although the site doesn’t permit comparisons of starters and relievers.

The big problem with comparing the leagues is context. It doesn’t help just to look at raw numbers, because the two leagues’ parks, and the DH, affect run scoring differently. The biggest issue is perhaps the ballpark contexts. Until recently, the PL was dominated by huge parks with vast outfields and high walls, where home runs were scarce and speed was at more of a premium. That has changed in recent years with the switch in the CL from small Hiroshima Citizens’ Stadium to more spacious Mazda Stadium, and by the Hawks and Eagles both decreasing the home-run distances by adding field seats inside the outfield wall.

If one looks only at the same main stadiums, and how each home team fares against visitors in league and interleague play in the same part of the season, then perhaps one can get a clearer picture. NPB’s interleague used to run from the middle of May to the middle of June, and now occupies the first 2-1/2 weeks of June in its new 18-game format.



Most speculation has been that PL pitching is superior. If that is the sole cause, one would expect the CL pitchers to do as well against visiting PL hitters in interleague as they do against visiting CL batters in May and June. To study this, a data set was constructed of all non-pitcher plate appearances in the 12 main parks in May and June from 2009 — when Hiroshima’s Mazda Stadium opened — to 2017.

The data does not prove PL pitching staffs and defenses are superior but suggests that may be the case, but it also indicates that PL teams are better at hitting, playing defense and have superior speed in the outfield.

Pitching

PL home teams scored 3 percent more runs per 27 outs against visiting CL defenses in May and June than against PL visitors. In contrast, the CL teams score 9 percent fewer runs in their home parks against PL visitors than they do against their regular CL rivals. These findings are consistent with the idea that PL pitching is superior.

Batting

The data suggests PL offenses are also better than those in the CL. CL home teams allow 4 percent more runs per 27 outs when the visitor is from the PL, while PL pitching staffs have far less trouble with visiting CL teams than PL visitors in May and June, allowing 14 percent fewer runs per 27 outs.

Fielding

In terms of getting hits on balls in play, home offenses in both leagues do better against interleague opponents who rarely visit their parks. The PL home batters had an edge in this area, a 3 percent increase in interleague batting average on balls in play, while CL home offenses’ BABIPs improved by 1 percent against PL visitors.

There is, however, a huge difference in what goes on when the visiting team is at bat in interleague play.

Visiting PL teams in interleague batted .310 on balls in play against CL home defenses that held their own CL league opponents to a .296 average. PL home defenses, on the other hand, surrendered a .306 BABIP to PL teams, a .290 BABIP to visiting CL teams.

Strikeouts

Like visiting defenses, hitters also seem to have trouble in the unfamiliar parks of their interleague opponents striking out more and walking less.

It’s at home where the difference is obvious. At home in interleague, CL hitters’ strikeouts rose by 13 percent against visiting PL pitchers, while PL hitters’ Ks were 2 percent less frequent when a CL club was in town.


Built for speed

One comment often heard about the PL teams is that they’re faster — especially in the outfield, a necessity in a league with lots of large turf outfields.  PL home teams allow 8 percent fewer doubles and 8 percent fewer triples against CL visitors than against PL visitors. Central League home teams surrender triples 8 percent more often against PL teams than against CL opponents.

When PL teams host interleague games, their batters’ triples and doubles increase. When CL teams host, their doubles and triples decrease.

Although PL teams appear to have a speed edge in interleague, the one area where CL teams actually do better is in preventing stolen bases. Stolen bases percentages go down for visitors in interleague, with the PL being hit slightly harder. At home, CL teams actually improved their stolen base success rate, while PL interleague hosts were less successful stealing bases than they were in league play.



The bunt, bushido and Japanese baseball’s issues with history

Japan’s home run explosion is making the obligatory sacrifice more and more of a stretch for NPB managers.

I love seeing a perfect bunt as much as the next fan, but hate the obligatory, let’s-take-a-bullet-for-the-sake-of-Japanese-winning-baseball-first-inning sacrifice as much as any of you, I’m sure.

Although the sacrifice bunt is celebrated as the epitome of Japanese baseball dogma, it’s popular now like it never was back in the day. Small ball has always been close to the heart of Japanese ball, but the bunt REALLY became popular in the late 1970s when former players of legendary Yomiuri Giants manager Tetsuharu Kawakami began taking over one NPB club after another.

The irony is that the bunt reached its most popular peak in the 1980s, when offense and home runs were at an all-time high and spearheaded by then Seibu Lions manager Tatsuro Hirooka. That’s when “the bunt IS Japanese baseball” was REALLY born. It’s not some age-old doctrine but a revisionist history — an explanation after the fact about how a policy that didn’t exist at the time of a perceived “golden age” was the secret to that era’s quality.

In that respect, Hirooka’s popularization of the bunt is reminiscent of Japan’s belief that bushido was a code warriors of a purer era lived by, when in fact it was a code meant as a wakeup call to men of samurai lineage who were warriors in name and social status only. It was a code that didn’t describe reality but was rather a set of moral ideals for warriors in a society without wars to aspire to.

Japan’s funny about the past. If one glorifies one’s famous predecessors, that goes over really well, whether it’s true or not. In fact, it’s something of a cottage industry that is hard to assail. If I tell you the Giants who won nine-straight Japan Series did so because of the sacrifice bunt, and you say it’s not true, your words can be perceived as criticism of a legend of the game.

The most famous example recent example of this was former BayStars skipper Hiroshi Gondo. The man, who asked his players to call him “Gondo-san” (Mr. Gondo) rather than Manager Gondo, was an iconoclast. He attacked a lot of Japanese pro baseball traditions as being moronic and a waste of time and was tossed out on his ear — despite a very successful run as skipper.

Yet, now, when more objective information is actually available, people will still argue that the first-inning sacrifice is key to winning games when it so obviously isn’t. But those days are numbered. It appears now that the current offensive explosion appears will finally drive the bunt’s arch proponents underground.

Digression aside, there has been a very peculiar relationship between win percentages and first-inning sacrifices.

Prior to the introduction of the deadened standard ball in 2011, see here and here, the relationship between wins and first-inning sacrifices favored visiting teams that bunted with no outs and a runner on first. From 2011 to 2016, home teams have done better bunting in the first inning of scoreless games with no outs and a runner on first.

Although the data this year is limited, in games through June 15, with home runs going through the roof in NPB like balls off Shohei Ohtani’s bat, the first-inning sacrifice by the No. 2 hitter appears to be approaching its final resting place.

In 71 games this season with a runner on first base in the top of the first, No. 2 hitters have had plate appearances ending in a bunt attempt (I have no record of fouled bunts before two strikes).

Yet, now, when more objective information is actually available, people will still argue that the first-inning sacrifice is key to winning games when it so obviously isn’t. But those days are numbered. It appears now that the current offensive explosion appears will finally drive the bunt’s arch proponents underground.

Digression aside, there has been a very peculiar relationship between win percentages and first-inning sacrifices.

Prior to the introduction of the deadened standard ball in 2011, see here and here, the relationship between wins and first-inning sacrifices favored visiting teams that bunted with no outs and a runner on first. From 2011 to 2016, home teams have done better bunting in the first inning of scoreless games with no outs and a runner on first.

Although the data this year is limited, in games through June 15, with home runs going through the roof in NPB like balls off Shohei Ohtani’s bat, the first-inning sacrifice by the No. 2 hitter appears to be approaching its final resting place.

In 71 games this season with a runner on first base in the top of the first, No. 2 hitters have had plate appearances ending in a bunt attempt (I have no record of fouled bunts before two strikes).

Visitors, 1st inning, Runner on 1B
2016: 187 chances, 54 attempts (29%) with a .537 win pct
2017: 57 chances, 14 attempts (25%) with a .357 win pct.

Home teams, 1st inning, Runner on 1B, scoreless game
2016: 194 chances, 77 attempts (40%) with a .622 win pct
2017: 58 chances, 11 attempts (19%) with a .364 win pct.