Nippon to MLB ERA Index

Willie Mays and Masanori Murakami

Since 1995 33 Japanese pitchers have come to the MLB from the Nippon League. Some pitchers found much success and others have been complete failures. The first Japanese pitcher to pitch in the United States was Masanori Murakami who pitched two seasons with the San Francisco Giants in 1964 and 1965. The next Japanese pitcher would not pitch in the United States until Hideo Nomo in 1995.

The first three years for a Japanese pitcher in the MLB are the transition years. These years are the years that show what kind of pitcher he really is. The last three years in the Nippon League are basically what Major League Baseball teams look at when deciding to sign the pitcher. By compiling statistics from the last three years in the Nippon League and the first three years in the MLB one can make an accurate comparison on how the pitcher performed.

Hideo Nomo

There are a few pitchers who came to the MLB from Japan without ever pitching in the Nippon League, they will not be included in the statistics, because this only focuses on the transition from the Nippon League to the MLB. By finding the total number of innings pitched and earned runs allowed in the Nippon League by pitchers in their last three seasons, you can find the ERA of the average pitcher coming to the MLB in his last three seasons in the Nippon League. This ERA is 3.06. Then by doing the same thing, but for the first three years in the MLB the for the average Japanese pitcher is 3.90.

With the known statistics you can create a ratio to get an estimate or understanding of how the average Japanese pitcher would perform in the MLB after playing in the Nippon League. This is 3.90/3.06 which equates to 1.275. So by multiplying a pitcher's ERA over his last three seasons in the Nippon league by 1.275, you will have an estimate of his ERA in his first three seasons the MLB.

Takashi Saito

This does not work out perfectly for every pitcher because it is an average, it is supposed to just provide an estimate. Hideo Nomo had a 3.29 ERA in his last three seasons in the Nippon league but a 3.34 ERA in his first three seasons in the MLB, but it turns out to work wonderfully to project Nomo for his career ERA of 4.21.  Now Takashi Saito who had a 4.65 ERA in his last three season in the Nippon League and had a 1.95 ERA in his first three seasons in the MLB. He did significantly better. These are just two pitchers the transitional index does not work for. They are not average pitchers. Saito was not that good in his last three seasons in the Nippon League and Nomo was better than most in his lasts three seasons. Before Daisuke Matsuzaka 27 pitchers came to the MLB from the Nippon League and I bet most of you cannot name more than 8.

Daisuke Matsuzaka

Speaking of Matsuzaka, the Nippon to MLB index has changed dramatically since he has come to the MLB. Since Matsuzaka the only Japanese pitchers to come to the MLB from the Nippon League are Kuroda, Uehara, Darvish, Iwakuma, Fujikawa, and Tanaka. These are all what I call "Super Star" players. The pitchers before Matsuzaka were not "Super Star" players. These guys are the ones that absolutely dominate the league and expect
huge contracts from Major League teams. In their last three seasons in Nippon League their ERA is 2.26 and in their first three seasons in the MLB 3.37. Significantly less than the average Japanese pitcher coming from the Nippon League.  The ERA index for a "Super Star" pitcher is 1.5.

Yu Darvish in last three seasons in the Nippon League had a 1.71 ERA. That would mean he should have a 2.57 ERA in his first three seasons in the MLB. He has a 3.21 ERA through his first two and a third seasons.

Yu Darvish

Hisashi Iwakuma had a 2.87 ERA in his last three seasons in the Nippon League. That would mean he should have a 4.30 ERA in his first three MLB seasons, but he actually has a 2.87 ERA in his first two and third seasons.

Masahiro Tanaka had a 1.44 ERA in his last three seasons in the Nippon League that means his ERA through his first three seasons in the MLB should be 2.16. In his first 11 games in the MLB he has a 2.06 ERA.

There are other pitchers you can see how they did and how they will do, but this basically tells us since Matsuzaka there has been less failure from Japanese pitchers coming from the Nippon League. If there is a "Super Star" pitcher in Japan meaning he has an ERA below 2.5 in Japan he is most certainly worth the money a team is willing to offer him. He should have an ERA from 3.18-3.75 which would mean an effective pitcher. If a pitcher has an ERA below 2.00 in the Nippon League he will have much success and little to no problems adjusting to the MLB.

Kenta Maeda

The next Japanese pitcher to come from the Nippon League to the MLB might be the right handed pitcher for the Hiroshima Carp, Kenta Maeda. He has a 2.05 ERA in his last three and a third seasons in the Nippon League. That means he should have a 2.61- 3.01 ERA in his first three seasons in the MLB. He is a "Super Star" pitcher. A few teams have heavily scouted him and he has expressed interest in playing in the Major Leagues.

 You can find a range for where the ERA of any Japanese pitcher in his first three seasons should fall by taking the average ERA of all Japanese pitchers and the average ERA of "Super Star" pitchers. So multiply the ERA in his last three seasons in the Nippon league by 1.275 and 1.5. The two numbers you get is an estimate of his ERA.

Masahiro Tanaka's First Start

Possibly the biggest story of the off season and spring training was Japanese phenom Masahiro Tanaka. After a dominating spring training and a long journey from his home country, Tanaka made his first start for the New York Yankees.

The $155 Million man. 

Tanaka's first start was against the Toronto Blue Jays on Friday night, and he was welcomed by the first batter he faced, Melky Cabrera, who hit a home run. After that home run he did get Colby Rasmus to gound out and proceeded to strike out Jose Bautista and Edwin Encarnacion. Tanaka made Bautista and Encarnacion look silly in these two at bats. Encarnacion would later get two hits off of Tanaka, but Bautista would be held hitless.

Although he never reached 100 pitches Tanaka was pulled after 7 innings allowing just 2 earned runs on 6 hits. He faced one of the best lineups in the American League on Friday and he proved to many what he could do. Tanaka did not get rattled after the home run, he kept his composure and proceeded to pitch a great game. His next start will be against another great lineup, the Baltimore Orioles, at Yankee Stadium.

Yankees Sign Masahiro Tanaka

Like many predicted the New York Yankees won the bidding war on Masahiro Tanaka, in part due to the fact that Alex Rodriguez's suspension was upheld. Tanaka will be pitching in New York under a 7 year $155 Million contract that contains an opt out clause after the forth season. Tanaka is 25 and compared to Clayton Kershaw who is also 25 Tanaka was just $60 Million shy of his deal making Tanaka the second largest contract given to a pitcher this off season.

Tanaka, as mentioned earlier is 25 years old and has already pitched 7 complete seasons for the Rakuten Golden Eagles in Japan. He has racked up 1315 innings in those 7 seasons which did concern many clubs, but I don't see it as a concern, I think he will make the transition nicely, just like Yu Darvish.

To compare Tanaka to Darvish, both pitched in the same league, Darvish for the Nippon Ham Fighters, so they have been facing the same players over the past few seasons. Yu Darvish also pitched seven complete seasons before coming to the United States and racked up 1268 Innings, so I do not see the concern with Tanaka pitching just 47 innings more. In his last three seasons Darvish pitched in Japan his ERA was 1.73, 1.78, and 1.44 respectively. He also averaged roughly 200 innings pitched per season those last three seasons. As for Tanaka the last three seasons he pitched his ERA was 1.27, 1.87, and 1.27 respectively. Tanaka averaged roughly 200 innings pitched per season those last three seasons as well.

The difference between Tanaka and Darvish is the fact that Davish has "strikeout stuff," but there is not enough significant evidence to support that claim. In Tanaka's career in Japan he had 8.5 K/9 and Darvish had 8.9 K/9, so they are actually statistically similar. Tanaka does feature a great splitter/slider combination and can reach 94-95 on his fast ball but averages around 91-92. Comparisons for Tanaka come to Hiroki Kuroda.

The Yankees needed pitching rather badly, and now they have four given arms in their rotation. Tanaka will likely take the third slot just to be safe behind Sabathia and Kuroda. The next step for the Yankees in this busy off season would to add to their bullpen and improve on their infield depth.