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As discussed by many pundits across MLB, there is an abundance of quality starting pitching in free agency this offseason. The free agents include big name players such as David Price, Zack Greinke, Johnny Cueto, and many more. However, there is one pitcher, in particular, who is flying under the radar as a highly effective pitcher in this year's free agent market. The pitcher is Hisashi Iwakuma. Iwakuma does not command a 95 MPH fastball like a David Price or Johnny Cueto. Neither does he have the name recognition of Zack Greinke as well. Yet, Hisashi Iwakuma has been an above-average pitcher the past three years and would prove to be effective option for a team looking for a quality #3 starter in the rotation.

WAR may suggest Hisashi Iwakuma regressed this season because of a 1.8 WAR in 2015 from a 3.8 WAR in 2014. Yet, it is important to take into account that WAR is an accumulation stat. For 2015, Iwakuma missed more than 2 months of the season with a lat strain in late April. After which, Iwakuma put together a fantastic year with a -1.07 ERPA (Top 25% of pitchers) and a 3.27 xFIP. The reason why Hisashi Iwakuma has proven to be an effective pitcher in the past three years (-0.87 ERPA) is not necessarily that he has the best pitching "stuff", but simply he is a smart pitcher on the mound. In the traditional Japanese manner, Iwakuma utilizes a splitter that demonstrates how he has been effective over the course of his MLB career.

Figure 1: Hisashi Iwakuma's Performance from 2013 to 2015

I personally like to imagine the fruition of Hisashi Iwakuma's splitter as the typical Japanese folklore on baseball. As Robert Whiting described the development of the forkball by former National League All Star and Rookie of the Year, Hideo Nomo, "he learned to throw his fearsome forkball,...developing his grip by wedging a tennis ball into the webbing between his index and middle fingers and taping it in place at night when he went to sleep." The forkball is slightly different to the splitter because of the grip of the pitch. However, this spreading of the fingers across the horseshoe of the baseball is pretty common amongst Japanese imported pitchers. The splitter is not just a magical pitch that fools hitters as described in baseball textbooks and novels. It is a pitch that requires strategy in order to be effective. Along the lines of Japanese narrative, the splitter fits the description of a pitch that can create deception with the right arsenal of pitches. In the case of Hisashi Iwakuma, he possesses a sinker, slider, and slow-curveball. By pairing the splitter with this arsenal of pitches, one can tell why Iwakuma has proven to be effective at the Major League level without the need for a 95 MPH fastball. The pitch can help not only induce a ton of groundballs, but it can make a batter feel unbalanced. Hisashi Iwakuma threw his sinker 36% of the time in 2015. Now, by mixing a splitter in 20% of the time, the significantly lower break and lower spin can throw off the timing of a hitter and help induce weak contact or even swing/misses.

Hisashi Iwakuma's Sinker vs. Splitter:


Figure 2: Iwakuma's Splitter (Light Pink) has the same horizontal break, but lower vertical break than his Sinker (Dark Pink)

The Mariners, recently, chose to place the Qualifying Offer, valued at $15.8 mill, onto Hisashi Iwakuma. With Iwakuma choosing to reject the offer, if he chooses to leave Seattle, a potential suitor for his services will have to forfeit a first round pick. Based on his current $13 million per year valuation, it would not make sense for a team to sacrifice a draft pick for an Average Annual Value (AAV) below the Qualifying Offer threshold and a pitcher going into his age 35 season. Yet, based on projections, Hishashi Iwakuma is a sure bet to perform to his above average expectations. I would not be surprised if a playoff caliber team swooped in and offered a contract for 2 years at $30 million.

Figure 3: Projection ERPA for 2016

1. "Baseball Statistics and Analysis | FanGraphs Baseball." Baseball Statistics and Analysis | FanGraphs Baseball. Fangraphs, n.d. Web. 15 Nov. 2015.
2. Pothula, Sanjay. "A New Form of SIERA: Pitcher Performance through the First Half of the Season." Ariball News. AriBall, n.d. Web. 15 Nov. 2015. .
3. Whiting, Robert. The Meaning of Ichiro: The New Wave from Japan and the Transformation of Our National Pastime. New York: Warner, 2004. Print.
NOTE: All statistics accurate as of 11/15/15

By Sanjay Pothula