Greinke and fly balls
In God we trust. All others bring data. -W. Edwards Deming
Along with Zack Greinke’s 2009 American League Cy Young Award came a widely-circulated article by Tyler Kepner in the New York Times. In the article, Brian Bannister is quoted, “So a lot of times, Zack would pitch for a fly ball at our park instead of a ground ball, just because the zone rating was better in our outfield and it was a big park.”
There’s quite a bit to digest in Kepner’s article besides that one excerpt from Bannister, but it was one piece that I thought would be easy to check. What did I find?
Road Home Bunt 5% 2% Fly 30% 33% Ground 36% 41% Liner 21% 16% Popup 8% 8%
The batted ball type comes from the MLB Gameday data. The results don’t really line up with what Bannister what saying. It may be that Greinke was pitching for more fly balls at home but not necessarily getting them, but that’s a question for another day.
Update: Here’s the batted ball log by game.
Date Park Fly Ground LD Pop Bunt 4/8 cha 0 8 2 1 1 4/13 kca 3 4 5 0 0 4/18 tex 6 9 7 1 1 4/24 kca 4 9 3 1 2 4/29 kca 9 6 2 1 0 5/4 kca 7 8 2 4 0 5/9 ana 10 9 2 0 2 5/15 kca 8 7 5 1 0 5/21 kca 5 8 2 1 1 5/26 kca 3 13 3 3 0 5/31 kca 7 11 2 1 0 6/5 tor 11 3 6 2 0 6/11 cle 3 8 5 2 3 6/17 kca 11 7 1 0 1 6/23 hou 6 14 3 0 3 6/28 pit 4 4 8 4 1 7/3 kca 5 9 3 2 0 7/8 det 7 6 2 0 1 7/14 sln 0 0 0 1 0 7/18 kca 4 11 2 3 0 7/24 kca 3 10 1 1 0 7/29 bal 6 3 4 3 0 8/3 tba 1 8 4 0 2 8/8 kca 6 8 5 3 0 8/14 det 6 4 5 3 0 8/19 cha 7 5 4 3 0 8/25 kca 7 4 1 1 0 8/30 sea 9 9 2 3 0 9/5 kca 9 4 8 1 1 9/11 cle 6 9 2 1 0 9/17 det 1 3 5 0 0 9/22 kca 8 3 2 2 0 9/27 kca 6 8 5 0 0 10/3 min 7 7 3 0 1
Can you find breakdowns for fly-liners? I thought the same thing about liners especially with the 5% swing in grounders
Hold up… think of the context. If Greinke’s thinking about ballpark effects, then obviously he’ll be doing that for each stadium he pitches in. Can you show the game-by-game log for this data? Perhap there’s 33% flyballs on the road because he pitched in a significant number of “flyball stadiums”?
Although I also find it very interesting that there’s a the higher rate of grounders on the road & lower rate of liners. That could indicate that many liners were interpreted as flyballs by the road game stats guy. There can be a thin line when it comes to some line drives & flyballs, as far as I understand.
But
I had the Home and Road columns switched, and I have now corrected that mistake. Not that it makes much difference to the conclusion.
I agree that there are all sorts of ways to parse the data, some of which I’m going to look at further. However, I found it interesting that at least on the surface there was no big disparity in batted ball types road vs. home for Greinke.
@OsandRoyals, I don’t have the BIS data with fly-fliner and liner-fliner breakdowns. I used the freely available Gameday data which just classifies flies and liners separately. I know the BIS fliner breakdowns are available at Fangraphs in the play-by-play logs, but I’m not eager to write a script to parse those into a database just for this question.
I’ve add the log by game to the post.
Pre-break (pre-Betancourt) he allowed 31% flies, 40% grounders, 18% liners, 7% popups, and 4% bunts. Post-break he allowed 33% flies, 37% grounders, 20% liners, 9% popups, and 2% bunts. All of his post-break starts were with Betancourt at shortstop except for October 3.
In my opinion, what’s interesting is Greinke’s first and second half splits of GB/FB. Around the ASB, the Royals acquired Yuniesky Betancourt and Jose Guillen suffered a season ending injury. These two factors combined to make the Royals infield defense worse and outfield defense better at approximately the same time. According to mlb.com, Greinke’s GO/AO ratio in the first half was 1.12, and in the second half it was 0.78, whether this represents an adjustment in strategy based on the change in the Royals’ defensive zone ratings or is an accident of small sample size is left open for interpretation.