When the Rakuten Golden Eagles announced that Masahiro Tanaka would be posted, Yankees fans everywhere (and fans of most every team, I suspect) rejoiced. This off-season has been tainted by the specter of the $189 MM payroll, and yet Tanaka offers hope that the Yankees may well renege upon their new found frugality (insofar as guaranteeing some $300 MM to Jacoby Ellsbury, Brian McCann, and Carlos Beltran can be considered 'frugal'). Throughout the off-season, there have been rumblings that the Yankees would be willing to break the bank for Tanaka, and Joel Sherman recently revealed that the front office would be willing go "way over" the $189 MM target, rather than brush up against it. Taken hand in hand, that sounds like a recipe for a Tanaka signing. For all of this, it does seem like the Yankees have gotten over the disaster that was Kei Igawa. After all, Tanaka has been a part of the blueprint for the team's off-season from the get-go. However, that has not stopped fans and media members alike from making comparisons to the ill-fated import, and hand-wringing over a narrative that begins and ends with nationality. I suppose it isn't entirely unreasonable, as the Yankees have been burned by two Japanese starters - lest we forget Hideki Irabu - and much of what has been written about NPB expatriates discusses the pitchers as "Darvish, and everyone else." While I will not entirely fault folks for falling prey to such misinformation, I do feel that it is appropriate to shed a little light on the relative success of Japanese starting pitchers.
The history of Japanese starters in Major League Baseball is rather sparse - only forty-one pitchers have come stateside, and only a dozen of those were starters for the majority of their career. We're starting off with a fairly limited sample size, which makes things rather difficult to analyze. That's all we have to work with, though, so it will have to do:
Hideo Nomo - 1976.1 IP, 97 ERA+, 2.8 bWAR per 162 Hiroki Kuroda - 1120 IP, 118 ERA+, 4.1 bWAR per 162 Tomo Ohka - 1070 IP, 105 ERA+, 2.6 bWAR per 162 Daisuke Matsuzaka - 707 IP, 100 ERA+, 3.0 bWAR per 162 Masato Yoshii - 757.1 IP, 101 ERA+, 2.3 bWAR per 162 Kazuhisa Ishii - 564 IP, 90 ERA+, 0.6 bWAR per 162 Hideki Irabu - 514 IP, 89 ERA+, 1.6 bWAR per 162 Mac Suzuki - 465.2 IP, 86 ERA+, 0.6 bWAR per 162 Yu Darvish - 401 IP, 127 ERA+, 5.9 bWAR per 162 Hisashi Iwakuma - 345 IP, 131 ERA+, 6.0 bWAR per 162 Kenshin Kawakami - 243.2 IP, 94 ERA+, 1.4 bWAR per 162 Kei Igawa - 71.2 IP, 68 ERA+, -0.9 bWAR per 162
All told, those dozen pitchers have combined to throw 8235.2 IP in the Majors, with a league-average-ish 4.26 ERA. Nomo, Kuroda, Matsuzaka, Darvish, and Iwakuma were all elite pitchers at one point or another, Ohka pieced together a run of above-average production with the Expos in the early 2000s, and Yoshii was essentially as average as could be. The rest showed flashes (save for Igawa), but were generally considered disappointments. Or, phrased differently, these dozen pitchers look an awful lot like any random sampling of starters over the last twenty or so years.
What does this all mean? Nothing. And everything. It demonstrates that our expectations of Japanese pitchers should be no different than those of any other pitching prospect. It reveals that our views should not be colored by previous disappointments from Japanese pitchers any more than the struggles of Phil Hughes should skew our views on Californian prospects. Simply put, it means that we should be scouting the player, and not the successes and failures of those who share his ethnic background.