Suppose that you have a strikeout pitcher and a non-strikeout pitcher, otherwise equal, pitching the same number of innings.   How many extra pitches does the strikeout pitcher throw, over the course of a season, because it takes more pitches to get an out by a strikeout?

            The best answer to that question, in my opinion, is “near zero”.   There are different ways to interpret the data, however, depending on exactly what you mean by “otherwise equal”, so I will put the data that I have on record and let you make what you will of it. 

            I got interested in this issue because of a discussion with John Dewan about one of his Stat of the Week items where he suggests that striking out batters leads to higher pitch counts because a strikeout requires more pitches. 

         To study the issue, I decided to form groups of pitchers, and to look at the number of pitches thrown by each group.   The groups of pitchers are:

            High Strikeout              High Walk

            High Strikeout              Medium Walk

            High Strikeout              Low Walk

            Medium Strikeout         High Walk

            Medium Strikeout         Medium Walk

            Medium Strikeout         Low Walk

            Low Strikeout              High Walk

            Low Strikeout              Medium Walk

            Low Strikeout              Low Walk

            How to form such groups?    I took all pitchers from the years 2002-2007, selecting those years because those are the years for which Bill James Online has pitch data.    I then trimmed this group to the 1102 pitchers pitching the most innings. 

            Why 1102, you asked?   I wanted to have a substantial number of pitchers in each pool—300—and I wanted to have “dead zones” between them so that something more than one strikeout or one walk separated the groups of pitchers.  I aimed for 1100, but there was a tie at the 1100 spot, so I included the two extras.

I then figured for each pitcher his strikeouts as a percentage of batters faced, and ranked the pitchers 1 through 1102 in terms of strikeouts as a percentage of batters faced.   The top 300 were “1”, the next 101 (301-401) were “2”, the next 300 (402-701) were “3”, the next 101 (702-802) were “4”, and the final 300 (803-1102) were “5”.   I then did the same for walks as a percentage of batters faced, again sorting the pitchers in groups 1 through 5.

            High Strikeout              High Walk                                was pitchers in group 1-1

            High Strikeout              Medium Walk                          was pitchers in group 1-3

            High Strikeout              Low Walk                                was pitchers in group 1-5

            Medium Strikeout         High Walk                         &​nbsp;      was pitchers in group 3-1

            Medium Strikeout         Medium Walk                          was pitchers in group 3-3

            Medium Strikeout         Low Walk                                was pitchers in group 3-5

            Low Strikeout              High Walk                                was pitchers in group 5-1

            Low Strikeout              Medium Walk                          was pitchers in group 5-3

            Low Strikeout              Low Walk                               ​; was pitchers in group 5-5

            While pitchers in groups “2” and “4”, either in walks or strikeouts, were excluded from the study.   “High strikeout/High Walk” pitchers thus were in the top 27% of all pitchers both in strikeouts and walks as a percentage of batters faced.

            I then sorted each group of pitchers by the number of batters faced, and took the 40 pitchers from each group who faced the most batters.   For those 40 pitchers in each group (360 total) I looked up the number of pitches thrown during the season.  (I initially did the study with 25 pitchers in each group, but the process of gathering the pitch data was fairly quick and painless, so I expanded it to 40, although 25 seemed to be adequate to provide stable data.) 

Peripheral Analysis

            Of course, the pitchers with the better strikeout to walk performance got better results.    This is the average performance of the 1,102 pitchers as a whole—9-9 record, .506 winning percentage, 4.41 ERA, 16% strikeouts, 8% walks:

            This is the average performance of the pitchers sorted into high strikeout, medium strikeout and low strikeout groups:

            The strikeout pitchers had a .566 winning percentage, 3.74 ERA; the low-strikeout pitchers had a .459 winning percentage, 4.91 ERA.   The high strikeout pitchers struck out 22% of the batters they faced, 148 batters on average; the low strikeout pitchers struck out only 11%, 73 on average.  This chart sorts the pitchers by into groups with high, medium and low walk frequencies:

            The pitchers with the highest walk rates had a .470 winning percentage with a 4.69 ERA.  The pitchers with the best control had a .548 winning percentage, with a 4.06 ERA. 

            There are two things about this data so far that are interesting.  First, strikeouts have more impact on the quality of performance than walks.   I did not expect this.  I would have anticipated that differences in walk rates would be more significant in driving pitcher effectiveness than strikeouts, and I would predict that if we did the same study for some earlier year—pre-1980—then walks would be the more important.  If my understanding is correct, then think what a historic shift we have undergone, as strikeouts have become more common.   It was always true—I believe—that the most important thing for a pitcher was control.  No more; as strikeouts have become more common, power has replaced control—at least in this data.  

            Second, strikeouts and walks are not closely related.   The walk percentage was actually 8.4% for the high-strikeout pitchers, 8.1% for the mid-group and 7.9% for the low-strikeout pitchers.   It shows at 8% all along; it was actually higher with the high-strikeout pitchers, but not much higher.    When sorted by walks, we have 16.7% strikeouts for the high-walk group, 16.1% strikeouts for the mid-walk group, and 16.0% for the low-walk group.   There is a connection between strikeouts and walks, but not much of a connection.  They’re pretty much independent variables.

            This data summarizes the performance of the pitchers in each of the nine groups; 1-1 is the High Strikeout/High Walk group, and 5-5 is the Low Strikeout/Low Walk group:

            The high-strikeout/low walk pitchers were 14-8 on average, .623 winning percentage, 176-42 strikeout/walk ratio.  The opposite-end group was 6-8 on average. .414 winning percentage, 5.24 ERA, 61-58 strikeout/walk ratio.

            That data is from the entire group of 1102 pitchers, excluding those who fall into one of the borderline categories.   This is the same data, but only for the 40 pitchers selected from each group:

            There are some differences due to the fact that this is only the pitchers who pitched more innings, thus there is a “quality screening” effect.  

            At this point I added to the data the numbers of pitches thrown by each pitcher.  The pitchers throwing the most pitchers per batter and the fewest pitchers per batter, among the 360 pitchers in the study, were:

            1.  Al Leiter, 2004                   4.33                 1.  Greg Maddux, 2007            3.26

            2.  Al Leiter, 2005                    4.25                 2.  Greg Maddux, 2002            3.27    

            3.  Chris Young, 2006              4.12                 3.  Greg Maddux, 2005            3.31

            4.  Chris Young, 2007              4.09                 4.  Carlos Silva, 2006               3.32

            5.  Geremi Gonzalez, 2003       4.08                 5.  Carlos Silva, 2004               3.33

            6.  Scott Kazmir, 2007 4.07                             6.  Josh Towers, 2005              3.37

            7.  Gil Meche, 2006                 4.07                 7.  Jason Johnson, 2005           3.38

            8.  Daniel Cabrera, 2006          4.05                 8.  David Wells, 2003               3.38

            9.  Gil Meche, 2005                 4.04                 9.  Roy Halladay, 2003 3.39

            10.  Matt Cain, 2006                4.04                 10.  Chien-Ming Wang, 2006 3.39

            Thus, we realize that throwing a large number of pitches (or a small number of pitches) per batter is a very pitcher-specific trait.   Gil Meche has quite ordinary strikeout and walk numbers, nothing remarkable about them.  He just uses a ton of pitches to do it.   There are other pitchers who have strikeout and walk numbers much higher than Leiter and Chris Young; they just do it with fewer pitches.   One suspects the Meche, Young and Leiter must be (or must have been) inclined to nibble on an 0-1 pitch or a 1-2 pitch, or inclined to simply waste a pitch down and away.    Otherwise it is hard to understand how why they would throw so many pitches. 

Analysis Central to the Research

Strikeout pitchers, on average, throw no more pitches per inning than do non-strikeout pitchers, at least within this data.   The average number of pitches per inning for the pitchers in these nine groups was:

  High Strikeout              High Walk                    16.72

            High Strikeout              Medium Walk              16.06

            High Strikeout              Low Walk                    15.16

            Medium Strikeout         High Walk                    16.88

            Medium Strikeout         Medium Walk              16.03

            Medium Strikeout         Low Walk                    14.97

            Low Strikeout              High Walk                    16.55

            Low Strikeout              Medium Walk              15.96

            Low Strikeout              Low Walk                    15.27

            Pitches per inning vary substantially with walks, but vary with strikeouts only to a small degree. The data above can be re-stated as follows:

            High Strikeout              Total                            15.98

            Medium Strikeout         Total                            15.96

            Low Strikeout              Total                            15.93

            High Walk                    Total                            16.72

            Medium Walk              Total                          ​  16.01

            Low Walk                    Total                          ​;  15.13

            How can this be, since we all know that a strikeout requires more pitches to accomplish than another out?   According to Pat Quinn of Baseball Info Solutions, the average strikeout requires 4.80 pitches, whereas the average non-strikeout at bat requires 3.53 (data is the same for either 2007 or the 2002-2007 period.) 

            But that’s a relatively small difference to begin with—a difference of 26% (3.53 ÷ 4.80 = .74), or a difference of 1.27 pitches.   But that difference applies only to the strikeouts themselves.  Even the high-strikeout pitchers strike out only 22% of the batters they face—and even the low-strikeout pitchers strike out 11% of the batters they face.  The difference is not 1.27 pitches per batter, but 1.27 * .11 pitches per batter, or .140 pitches per batter. 

            But this effect is off-set, on a per-inning basis, by the fact that the strikeout pitchers are more effective, and thus are able to complete their innings while facing fewer batters.   The net effect is that strikeout pitchers throw no more pitches per inning than do non-strikeout pitchers.

            One can see a difference, as noted, in pitches per batter.   Repeating the charts above, but with pitches per batter replacing pitches per inning, we have:

  High Strikeout              High Walk                    3.92

            High Strikeout              Medium Walk              3.83

            High Strikeout              Low Walk                    3.71

            Medium Strikeout         High Walk                    3.82

            Medium Strikeout         Medium Walk              3.74

            Medium Strikeout         Low Walk                    3.59

            Low Strikeout              High Walk                    3.69

            Low Strikeout              Medium Walk              3.65

            Low Strikeout              Low Walk                    3.59

            High Strikeout              Total                            3.82

            Medium Strikeout         Total                            3.72

            Low Strikeout              Total                            3.64

            High Walk                    Total                            3.81

            Medium Walk              Total                            3.74

            Low Walk                    Total                            3.63

            Stated per batter, the effect of strikeouts in driving pitch counts upward is essentially the same as the effect of walks.   Since walks, of course, have no “out value”, they are simply an addition to the load when stated on a per-inning basis, which causes walk totals to dominate the data stated by innings. 

            So if what you mean by “other things being equal” is that you have two pitchers who each face the same number of batters, then yes, the strikeout pitcher will throw some extra pitches.   How many?   About 100 to 150 extra pitches per year, for a healthy starting pitcher.   I don’t think that is what most people mean by “other things being equal”.   I think when we think of a pitcher with 220 inning pitched, we tend to think of that as being equal to another pitcher who pitched 220 innings, not to a pitcher who pitched 205 innings but faced the same number of batters. 

            The other comment made by John is that “strikeout pitchers are more prone to control problems.”   Historically, this has been true, and it remains true now if you focus on pitchers pitching a limited number of innings. 

            In modern baseball when you are talking about pitchers pitching 150 or more innings, there is little connection between strikeouts and control problems.    I looked at all pitchers pitching 150 or more innings:

            a)  from 1920 to 1935,

            b)  from 1950 to 1965, and

            c)  from 1998 to 2007.

            From 1920 to 1935 there were 1,140 such pitchers.   Comparing the top 20% of those pitchers in strikeouts/nine innings to the bottom 20%, the top strikeout pitchers walked 20% more hitters (20.1%, as a percentage of batters faced). 

            From 1950 to 1965 there were 1,053 such pitchers.  Comparing the top 20% of those in strikeouts/nine innings to the bottom 20%, the top strikeout pitchers walked 16%

more hitters (15.5%).

            From 1998 to 2007 there were 975 such pitchers.  Comparing the top 20% of those in strikeouts to the bottom 20%, the top strikeout pitchers walked 8%

more hitters (7.8%). 

So. . .yes, strikeouts do connect to walks, but not really, in the modern game; not the way they did when you and I were young, Maggie. It used to be that there were some pitchers who were playing for strikeouts, and those pitchers sometimes walked batters because they were trying to strike them out.   In the modern power vs. power game, it is more true that everybody is playing for strikeouts, and thus that walk rates simply represent control.   It used to be an option; now that’s just the way the game is played. 

By the way, John Dewan did some research as well and found this:

Using the top five starters on each team (based on games started), we get 150 Major League Baseball pitchers from 2007.  We divide them into three groups of 50 based on their Strikeouts Per Nine ratio.  Here is how it comes out:

                                  ​ Innings      BB/9  K/9   Pitches/Inning

High Strikeouts             8,716         3.1     8.1      16.28

Medium Strikeouts        7,442         3.0     6.2      16.19

Low Strikeouts              7,332         2.8     4.6      15.81

So there is a pattern.  Strikeout pitchers do throw more pitches.  But it's minimal.  Over the course of 7 innings, the high strikeout group throws 114 pitches, medium throws 113 and low throws 111.  That's a difference of only three pitches per game from the top group to the bottom.  Which, interestingly coincides pretty much with the extra pitches thrown on the 3-4 extra strikeouts those pitchers get.

So, we're back to where we started.  Strikeout pitchers do throw extra pitches, but not very many, and not anywhere near as many as most baseball observers might think.

            It’s a matter of perspective, I suppose.   From now on, when I hear somebody say that strikeout pitchers throw more pitches because the strikeout requires three pitches to get an out, I plan to say, “that’s really not true.”   If you want to interpret the data differently, I guess that’s up to you.