- Over career, strong relationship between hits per nine and FIP
- Therefore increased H/9 increases FIP
- Strong relationship exists between hits per nine and line drives per balls in play versus sinkers (Higher LD/BIP leads to higher H/9)
- Set career high in LD/BIP in 2015 on sinkers
- Strong relationship exists between hits per nine and line drives per balls in play versus sliders (Higher LD/BIP leads to higher H/9)
- Set career high in LD/BIP in 2015 on sliders
- Strong relationship exists between hits per nine and line drives per balls in play versus sinkers (Higher LD/BIP leads to higher H/9)
- Therefore increased H/9 increases FIP
- Over career, strong relationship between whiff rate on sinkers and strikeouts per nine
- Set career low in whiff rate on sinkers in 2015
- In 2015, recorded lowest average velocity on fastball
- Recorded highest career FIP against leftie
- Recorded lowest career ground ball rate
Explanation of Findings
Over Jeff Samardzija’s career there has been a strong correlation (R value of 0.963621895) between his hits surrender per (H/9) and FIP (defined as fielding independent pitching, measures a pitcher’s effectiveness at limiting homeruns, walks, and hit by pitch and causing strikeouts). Therefore I sought out to find reasons why his H/9 may have increased in the 2015 season as this could explain why his FIP was elevated during the year. One possible explanation for why his H/9 increased was that Samardzija posted career highs in terms of line drives per balls in play (LD/BIP) for both his sinker and slider. As he throws these two pitches approximately 46% of the time, they play an important role in his pitch arsenal. Over his career the LD/BIP of these two pitches have demonstrated a relatively strong correlation with his H/9 (R=870057957 for his sinker and R=0.739547925 for his slider). Therefore because of this correlation, it can be assumed that his increased H/9 can be explained in part due to the increased LD/BIP of his sinker and slider. The next question then, is why did the LD/BIP increase. For his sinker it can be explained by a decrease in the velocity. In 2015, the average velocity of his sinker was 94.95 mph a decrease of 0.67 mph from the career peak. For his slider, the increase in LD/BIP can be explained, in part, by the fact the he threw the pitch for a lower percentage of strikes. This in turn decreased the whiff percentage and led to more balls being put into play. This led to the higher LD/BIP for his slider.
Another factor which contributed to Samardzija’s struggles was a decrease in whiff rate on his splitter, reaching a career low. Over his career the splitter has been his “strike out” pitch. There is a strong correlation between the whiff % on splitters and strikeouts per nine (R=0.934841935). Because of this it explains why his strikeouts per nine and total strikeouts reached career lows. A lower strikeout rate negatively affects pitchers as it makes it more difficult for them to get out of high leverage situations. This can often lead to more earned runs and longer at bats. Both of these factors could have contributed to Samardzija’s struggles in 2015.
In 2015, Samardzija also recorded career lows in velocity on his four seam fastball. At an average of 94.29 mph, it was 1.85 mph slower than his career peak. This is troublesome because there is a strong correlation (R= 0.870792943) between fastball velocity and line drives per balls in play of fastballs. Though this does not appear to have affected any of his stats directly in 2015 it is a troubling trend. Samardzija could be described as a power pitcher and often relies on his velocity in order to record outs. Therefore, decreasing velocity could spell more problems for him in the future.
There were other factors which may have been out of Samardzija’s control which led to his struggles throughout the season. For example, during the 2015 season Samardzija recorded his highest career FIP against lefties. One thought I had was that his struggles against lefties could be explained by the fact that in the American League the lefty hitters are better. However, there is no data to conclusively back this up as lefties in the American League hit .256 against right handed pitchers and lefties in the National League hit .263 against right handed pitchers. So saying that his struggles against lefties can be contributed to the league he pitched in does not seem to be a valid theory. To me, it seems that his struggles against lefties can be attributed at least in part to bad luck. For example, in 2015 he surrendered 21 homeruns to lefties compared to 9 in 2014. While some of these homeruns can be explained by decreasing velocity and a lower strikeout rate, there is an element of bad luck that came into play as well. Another issue which plagued Samardzija in 2015 was a decreasing ground ball rate. In 2015, he posted a Ground Ball rate of 39%, down from 50.2% in 2014. This decreasing ground ball rate led to a higher average against and also in part to a higher HR/9.
What it Means
All together, there are some worrying trends for Samardzija. His decreasing velocity on both his fastball and sinker could cause problems in the future. However, compared to most pitchers who are hitting free agency for the first time, Samardzija has very low mileage on his arm. Therefore, in theory, the continuing decrease in velocity should be relatively low over the next few years. The other aspects which worry me the most is the decreasing strike out rate and decreasing groundball percentage. These worry me the most because both of these lead to high percentage outs. Obviously a strikeout leads to an out but ground balls tend to lead to more outs as well and are also less dangerous than fly balls. But not all is lost for Samardzija. He is still young and has had no serious health problems throughout his career. Some of his struggles in 2015 can be explained by bad luck and they should not repeat themselves in 2015. Other struggles, such as his decrease in percentage of sliders thrown for strikes, can be fixed. Also, at the end of the season he pitched two fantastic games showing that he can once again be the pitcher he was in 2014. All these factors will come into play when teams decide if they want to sign Samardzija this offseason. I expect him to receive offers in the same range as James Shields did in 2014, around $75 million over four years. He may not fully reach the $75 million ($65 million over four years may be more likely) though, as he is coming off of muc a worse season than Shields was in 2014. However, Samardzija also has the element of youth on his side as he is 30 years old while Shields was 32 years old when he signed. Both have similar career stats and Samardzija showed glimmers of hope that he could still be a number one, number two pitcher. All in all, I expect Samardzija to have a much better in 2016 season than he did in 2015, albeit probably not in a White Sox jersey unfortunately. Though he may not recreate the numbers he did in 2014, I expect him to pitch at least closer to his career norms.
Notes
- Sources
- http://www.baseball-reference.com/players/s/samarje01.shtml
- http://www.fangraphs.com/statsplits.aspx?playerid=3254&position=P&season=2012
- http://www.brooksbaseball.net/tabs.php?player=502188&p_hand=-1&ppos=-1&cn=200&compType=none&risp=0&1b=0&2b=0&3b=0&rType=perc&time=month&minmax=ci&var=so&s_type=2&startDate=01/01/2013&endDate=01/01/2014&gFilt=regular
- Used FIP over ERA as I feel it better represents how well a pitcher pitched. Helps to eliminate a team’s poor defense from the equation.
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