Of the 81 pitchers who reached the 162-inning threshold necessary to qualify for the ERA title, 19 had an average fastball velocity of less than 90 MPH. In a league where scouting is often performed with the radar gun, are these pitchers effective? If so, how?

The traditional conception of a pitcher with below average velocity is that of a back of the rotation innings eater, or in other words, a below average starting pitcher. This was not the case in 2013 as this group averaged a 3.80 ERA, which is slightly less than the 3.87 league mark. How did this group manage to not only merit a roster spot but collectively prevent runs better than the league average rate?

The chart below shows the average fastball velocity of each of the 19 pitchers on this list that we will be examining.

To answer these questions, I examined the statistics of three groups of pitchers.

1. Qualified pitchers (162 IP) with average fastball velocities below 90 MPH, which we will call the sub-90’s group.
2. All qualified pitchers.
3. The league average.

All members of the first two groups are primarily starting pitchers (Jerome Willams was the lone swingman to qualify) while the league average includes both starters and relievers.

Traditional Statistics

The chart below shows traditional statistics of each of these three groups. Some of the counting stats are omitted in the league average for obvious reasons.

It's odd that members of the sub-90s group are traditionally referred to as “inning eaters”, yet they average almost exactly the same amount of innings pitched as the rest of the qualified starters. James Shields and Justin Verlander seem to be much better candidates for the innings eater label than anyone in the sub-90s group. Perhaps this label is instead reserved for those who eat innings but offer little else, but either way, there seems to be little correlation between innings pitched among qualified starters and velocity.

The same appears to be true regarding wins and losses.

The differences in this data set are found in strikeouts, home runs, and ERA. We have already mentioned that the ERA of the sub-90s group is better than league average, but worse than the average of the qualified starters. This seems to imply that the group of qualified starters is the most effective of these three groups, followed by the group of qualified starters with sub-90s fastballs, with the league average pitcher coming in last.

These differences between the group of all qualified starters and those with sub-90 fastballs are supported by the difference in home runs and strikeouts. It doesn't come as much of a surprise that the sub-90s group strikes out fewer batters than their hard throwing counterparts.

The home run totals for the sub-90s group are inflated due to extremely high marks of 36 by A.J. Griffin, 35 by R.A. Dickey, and 32 by Bronson Arroyo. Nine of the pitchers in the sub-90s group surrendered fewer home runs than the average of all qualified starters meaning that the inflated home run mark of the sub-90s group results from a few extraneous variables much more than a significant trend.

Observations and Conclusions from this section

1. Members of the sub-90s group should not be referred to as innings eaters.
2. Members of the sub-90s group strike out fewer batters than members of other groups.
3. The high home run totals of the sub-90s group are the result of extremely high totals from a few pitchers and not a general trend.

Rate Statistics

These rates are largely unsurprising and confirm the assertion from the previous section that of the three groups, the average qualified starting pitcher is best, followed by the average member of the sub-90’s group and finally the league average pitcher.

It makes sense that the K rate of the sub-90s group is lower than the rest and it also makes sense that their BB rate is lower than the rest. Since these pitchers lack power, they must make up for it with movement and control. The latter of these attributes is evident in the walk rate that is nearly two percent lower than league average.

As described before, the sub-90s group has a few members who are abnormally prone to home runs, which brings the rates of the entire group down. However, those with high home run rates have found other ways to counteract their combination of poor velocity and poor home run rates. A.J. Griffin and R.A. Dickey held opposing hitters to an extremely low AVG, while Bronson Arroyo posted the second-lowest BB rate in the group at 4.10% (Bartolo Colon’s 3.80 mark was best).

The difference in BABIP between the three groups is relatively small, but the difference in K rates widens the gap in AVG Against, as AVG against is a result of BABIP and K rate. This demonstrates the value of the strikeout as a sure out that is not subject to the variance of balls in play. The low BB rate of the sub-90’s group lessens this gap in OBP Against.

Observations and Conclusions from this Section

1. Members of the sub-90s group walk fewer batter than members of the other groups.
2. Confirmation of conclusion three from the previous section: The high home run totals of the sub-90s group are the result of extremely high totals from a few pitchers and not a general trend.

Pitch Data

The following data show the value of each pitch from each group of pitchers. CT stands for cut fastball and SF stands for split-fingered fastball. The first listed statistic for each pitch, which features the pitch abbreviation followed by a lowercase v, stands for the velocity of each pitch. The second statistic is the usage of each pitch as a percentage of the total number of pitches thrown. The third and likely most unfamiliar statistic measures the value of each pitch per 100 pitches.

Before jumping to conclusions with this data, keep in mind that R.A. Dickey’s profile as a knuckleballer skews the pitch selection for the sub-90s group more than the group of all qualified pitchers. Excluding Dickey, the pitch selection for both groups is listed below.

It's no surprise that the velocities of the sub-90s group are lower than the velocities of each of the other groups in every pitch category, but the usage patterns are interesting. The average qualified starting pitcher throws his fastball significantly less than the league average pitcher, and the average starting pitcher with a sub-90s fastball throws his fastball even less than that. This makes sense and confirms the conventional wisdom that a starting pitcher must have three effective pitches but a reliever must only have two, thus starting pitchers will throw each pitch less frequently.

The data also show that the sub-90s group is also extremely likely to rely heavily on a cut fastball even though it proved to be the least effective collective pitch from the group. Of the 19 pitchers in the sub-90s group, 10 throw a cut fastball with six throwing the pitch at least 20% of the time.

The split-fingered fastball is used by only four of the 19 pitchers in this group, but is used extensively among three of them. Hisashi Iwakuma throws his split-fingered fastball 22.8% of the time, followed by Ryan Dempster at 17.7%, Dan Haren at 16.9%, and Scott Feldman at 4.6%. For these four pitchers the split-fingered fastball serves as a replacement for a changeup as none of them throw the pitch. Only two qualified pitchers, Ubaldo Jimenez and Yu Darvish, threw both pitches during the 2013 season. Each of the other 79 qualified pitchers chose between one pitch or the other. Justin Masterson came the closest to throwing neither pitch as he did not throw a split-fingered fastball and only threw his changeup 0.1% of the time.

Conventional wisdom holds that those who lack fastball velocity must overcome this deficit by effectively changing speeds and locating well, but evidently this notion is far from accurate. We have already established that control is an area where the sub-90’s group excels but what about the other aspects of these common assumptions?

Let’s examine these one at a time, beginning with the assumption that a harder fastball is necessarily a better fastball, then examining the tendency of members of the sub-90s group to change speeds more frequently.

The data shows that the correlation between fastball velocity and wFB/C among qualified starting pitchers was a mere 0.28 (where 0 means no correlation and 1 means perfect correlation). The sub-90s group fared extremely well in the value rankings of the pitch, as Iwakuma’s fastball was the 12th most valuable among qualified starters last season while Colon’s came in 15th, Wood’s came in 16th, and Fister’s came in 19th. Moving to the bottom of the list, Bronson Arroyo’s sub-90s fastball was the least valuable, followed by Edwin Jackson's 93.1 MPH heater.

Wily Peralta's 94.8 MPH fastball, the fourth hardest among qualified starters, was the eighth worst fastball among the same group. It seems that the proper conclusion from this data is that high velocity is better than low velocity but velocity is not the only factor necessary for an effective fastball. It is certainly possible to have a good fastball with poor velocity and a poor fastball with good velocity. However, the very best fastballs are thrown with good velocity.

To analyze the second common assumption, the tendency of the sub-90s group to change speeds more frequently than their hard throwing counterparts, we can combine all pitches into two categories: hard stuff and soft stuff. Hard stuff consists of all types of fastballs, including cut fastballs, and soft stuff contains everything else. R.A. Dickey’s numbers are excluded from the data of the sub-90s group and the group of all qualified starters.

(Due to rounding, these numbers may not add up to exactly 100%)

Conventional wisdom holds that pitchers lacking velocity tend to throw the metaphorical kitchen sink at a hitter, typically featuring soft stuff followed by more soft stuff, but evidently this is not the case. It is no surprise that both groups of qualified starting pitchers throw more soft stuff than league average, but it's a surprise that the sub-90s group throws hard stuff at a higher rate than the group of all qualified starting pitchers.

The group of all qualified starters throws their fastball at a higher rate than the sub-90s group, but the sub-90s group more than overcomes that deficit through use of the cut fastball. The fastball and cut fastball combination is often reserved for power pitchers and it is extremely interesting that the sub-90s group has similar pitch selection.

Observations and Conclusions from this section

1. The sub-90s group relies on cut fastballs and split-fingered fastballs much more than the other groups.
2. The sub-90s group throws hard stuff more often than the group of all qualified pitchers.
3. Premium velocity does not necessitate a good fastball and poor velocity does not necessitate a poor fastball. It is possible to have a good fastball with poor velocity and a poor fastball with good velocity.
4. The very best fastballs are thrown with good velocity.
5. Almost every pitcher chooses a split-fingered fastball or a changeup but not both.
6. Qualified pitchers in both groups throw fastballs less frequently than league average.

Batted Ball Statistics

The most obvious conclusion from this set of data is that the sub-90s group allows more fly balls, less ground balls, and slightly less line drives than any of the other groups. This is somewhat surprising as pitchers with good sinkers are generally the best ground ball pitchers, and sinkers are generally slower than most fastballs (but are still categorized as fastballs).

These group averages are somewhat skewed because of the extreme fly ball tendencies of A.J. Griffin, Travis Wood, and Dan Haren. This is a somewhat small sample size of 19 pitchers, so each member of the sub-90s group has considerable influence on the group averages.

I believe that this set of data is indeed skewed for a couple of reasons. First, if we exclude the three pitchers with the lowest GB rates and the three pitchers with the highest GB rates from the sub-90s group, the average of the remaining 13 pitchers is 44.0, which is closer to the 44.9 mark from the group of all qualified starters and the 44.5 league mark.

Second, if we examine the trend of individual pitchers rather than the average, it's clear that this is a fluke. Of the 19 pitchers in the sub-90s group, nine have GB rates lower than 42.61, but another nine have GB rates higher than 45.29, which is higher than the average of either group. Bronson Arroyo’s 44.40 GB rate is the only one close to the average.

This means that members of the sub-90s group are not less likely to be ground ball pitchers than members of any other group, but members of the sub-90s group who are not ground ball pitchers are more likely to allow extremely few ground balls.

The consequence of a fly ball profile is an inflated home run percentage, shown again in this section for reference. This inflated percentage is a direct result of both the high fly ball rate and the close to league average HR/FB rate of 10.43, which is much higher than the rate of the group of all qualified pitchers.

Observations and Conclusions from this section

1. The high average fly ball rate of the sub-90s group coupled with their high HR/FB rate lead to their high HR%.
2. Despite the low average GB rate of the sub-90s group, members of this group are not more or less likely than members of any other group to have a GB rate lower than league average.
3. Members of the sub-90s group with lower than average GB rates are more likely to have extremely low rates.

Sabermetric Statistics

Each of these statistics is composed of previously mentioned statistics, but they are still useful as a means to draw larger conclusions. The main conclusion here is the inflated FIP, xFIP, and SIERA of the sub-90s group leading to their -0.16 E-F (ERA-FIP) mark, which means that good fortune may have played a role in their impressive ERA totals.

FIP considers only the “three true results” of strikeouts, walks and home runs, implying that balls in play are somewhat out of the control of the pitcher. This is a useful but flawed statistic, as pitchers do have some control over the types of batted balls hit against them. xFIP uses the same formula as FIP but replaces home run rate with the 10.5% league average HR/FB rate, which is useful for removing the luck factor from home run rate.

An easy explanation for why the sub-90s group outperforms their FIP and xFIP could be their batted ball types but this is not the case. This group has poor results in two of the three true results (low K’s and high HR’s) and two of the three batted ball types (GB rate and FB rate). This is considered in SIERA, which stands for Skill Interactive ERA, and utilizes both batted ball data and three true result data to create a metric on the ERA scale that a pitcher with a specific skill set ought to deserve. The SIERA totals also shows that the sub-90s group has been the beneficiary of good fortune.

It seems strange that the sub-90s group would post a FIP, xFIP, and SIERA higher than league average, but an ERA lower than league average. LOB% is not the answer as both groups of starters stranded roughly 74% of their runners. Almost every other relevant statistic that could explain this phenomenon has already been discussed, meaning that this must be presented simply as an existent phenomenon without explanation.

Observations and Conclusions from this section

1. Sabermetric statistics indicate that the sub-90s group lacks the skill set of pitchers deserving of a 3.80 ERA.
2. It is unclear how the sub-90s group managed to post such a good ERA in spite of their poor peripheral statistics.

Final Thoughts

Earning a spot in a major league rotation with a sub-90s fastball is quite an accomplishment, and these pitchers have found many ways to do so. Bartolo Colon survives by relying on his fastball more than any other qualified pitcher in the league, while R.A. Dickey and his extreme use of the knuckleball helped him win the 2012 NL Cy Young Award. Hisashi Iwakuma used his tremendous split-fingered fastball to become a finalist in the 2013 AL Cy Young Award voting, while Joe Saunders, who was poor in almost every pitching statistic, continues to occupy rotation slots due to his experience (he beat Yu Darvish in the inaugural AL Wild Card Game).

There are certainly general trends among these 19 pitchers, such as limiting walks, but there are many ways to survive in the major leagues without a 90 MPH fastball. These 19 pitchers are vastly different but each finds ways to be effective in their own, generally slightly unorthodox way.

Velocity is certainly beneficial to a pitcher but I believe that this study proves that success can be had without velocity and velocity can be had without success.

Source: Fangraphs.com