Hitting More Foul Balls Equals Success: 2014 and 2015 MLB Averages Compared


Two seasons ago (2014) in “Is Fouling Off Pitches a Skill?”, Eno Sarris discussed the idea of the two-strike approach, asking in response to Sam Fuld’s questions about foul ball percentage, if the best hitters have some advantage at the plate as they face a two strike count. That’s the gist anyway. Sarris finds little evidence to indicate there is. But he and Fuld may have been looking at it all wrong. But hitting more foul balls is a skill.

Indeed, during the turn of the 20th century, many sources report that players had become adept at fouling off balls; this was before the foul ball actually counted as anything more than a dead pitch. Prior to 1900, in fact, players started becoming skilled at foul ball hitting in order to draw a walk. The historical data certainly impresses upon us that such a skill does exist. Players like Rickie Ashburn were known to have this ability as late as the early- to mid-1900s.

Current data over the 2014 and 2015 seasons supports this idea too: Slapping away pitches does appear to be a skill when the foul ball rates of the top hitters are compared to those of the bottom hitters.

As is typical of baseball writers and statisticians, when we think of batting stats we always go to the defaults—batting average, WAR, OPS, etc. We also look at the number of at-bats, runs and number of and how many hits. But we fail to consider the as-important state of FABs (Fouls/At-Bat). Sarris used IncreaseFoul% for this analysis. FAB (the percentage of times a batter gets on base via a BB, 1B, 2B, 3B or HR after hitting at least one foul ball in the at-bat), however, as a statistic is as valuable as any of the others. And is the one that Sarris and Sam Fuld overlooked (mainly because I just made it up). In order to test whether there was a difference in percentages, in 2015 I altered the test to the current method (number of times batter got on base through conventional means/at-bats with foul balls). This is a derivation from the 2014 season which looked at the number of foul balls hit in conjunction with offense generated in the form of a BB, 1B, 2B, 3B or HR, and presents a more accurate conversion rate.

The results are very similar.

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2014 Data Shows Significant Differences in Foul/On-Base Rates

First, looking at the top 10 averages from 2014 and comparing them to the bottom ten we see why the top players are so good. We forget there’s a reason they are the top batters. FAB is the reason.

A quick peek at the numbers between Chris Davis, the 2014 player with the worst batting average after at least 400 at bats, and Jose Altuve, the best average, we see what appears to be a modest 25 foul ball difference. However, when we calculate the percentage of times Altuve gets on base with a non-intentional walk, a single, double, triple or home run versus Davis, we can see the true differences. Altuve is able to get on base 5.18% more often after hitting at least one foul ball than Davis.

This 5% difference between Altuve and Davis isn’t an exception; rather, it is the rule. Foul ball average conversation rates in 2014 between the players with the best and the worst batting averages were staggeringly different. Not only did the players with the best averages slap away more pitches for fouls per at bat, they had a considerably higher conversation rate for Unintentional Base on Balls, Singles, Doubles, Triples and Home Runs. It is this difference that helps make the best the best and the worst the worst. It is a pronounced 4.03%. This conversation rate would also partially account for the 800 additional balls the top 10 averages saw last season.

At the end of the 2014 season, the ten best and the ten worst batting averages looked like this:

Best v Worst Chart_Page_2 Best v Worst Chart_Page_1

What I’ve discovered in my research into FAB rates is that the top ten hit more foul balls with a conversion rate that is just over 4% higher than the bottom ten averages last season; that’s roughly 350 more times on base than the bottom ten. The top ten slapped away more fouls and converted more of those at bats:


2015 Averages Show Similar Outcomes

The results for the top and bottom for the 2015 season show the same results. While I altered the formula ever so slightly, the final percentages speak volumes. It is clear that, regardless of what the formula is, the top 10 averages do generate 5-6% more offense after slapping away at least one foul ball as opposed to the bottom 10. The top 10 averages also have more over 400 more at-bats with at least one foul ball.

Best v Worst Chart 2015_Page_1 Best v Worst Chart 2015_Page_2

As seen in the charts, the top 10 averages in 2015 (those hitters with 400 or more plate showings) averaged getting on base over one-third of the time after swatting away a pitch, or 33.5% of the time. The bottom 10, however, were only successful barely one-fourth of the time, or 27.2% of the time.


Why the Numbers are Important

There are a few probable reasons for this significant FAB difference, reasons that Sarris and Fuld overlooked:

    • The batters with the higher averages swing at closer pitches.
    • Top averages see more pitches as a result of swinging at closer pitches OR the setup of the system equates to more at bats naturally. This places the bottom of the order at a distinct disadvantage.
    • They are more skilled at—contrary to Eno Sarris’ conclusion—fouling off close pitches, not necessarily in JUST a two-pitch count.

In other words, slapping away pitches is a skill. The ability of the top averages, for whatever reason, to clearly be able to foul off more pitches at a consistently higher FAB indicates a 5% higher rate in the two studies from 2014 and 2015, indicates a skill.

It’s no accident that the best are the best; they are able to shrug off more pitches than the lower averages in order to get to “their” pitch. This works to their benefit in many ways. The most obvious is they see more pitches as a result of their skill in slapping away close pitches; this increases their odds of getting on base because they obtain a better understanding of pitch speeds and locations a pitcher is favoring. Fouling off more pitches also wears out the pitcher’s arm more quickly. Given that few teams have anything more than average bullpens, driving up the pitch count early in this era of 100 pitches is important.

As I mentioned above, in the years before the foul ball became a 1st and 2nd strike and an out, guys had become rather adept at intentionally fouling off pitches. That ability is one of the main reasons the rule was changed. In some ways, the best batters of the modern era have developed a similar ability, though limited due to the first two fouls now counting as strikes and the potential for an out.

The fact that the top 10 hitters are averaging foul ball offense at a rate 5% higher than the bottom 10 offers a lesson to the bottom 10 on how they might improve. Often, we see batters stand and watch pitches. There’s an old saying in baseball that states you should swing away. This certainly appears to be the case when we look at the FAB results. A poor batter, simply put, should be swinging at anything close.

The one issue is that the skill is developed. Elite hitters are able to pick up the seams of the ball more quickly and adjust to what they see more quickly than the average and below average hitters. But even if the bottom 10 need to better develop this aspect of the skill, simply swinging at a pitch they feel is close, could help them in the long run, if for no other reason than to wear down the pitcher a little more quickly.

My advice for the bottom ten: If you even think it’s close to a strike, swing. The worse that can happen is nothing. Given that swinging at pitches drives up pitch counts, helps batters assess pitch types, speeds and locations better (take a “the more you see the more you understand” mindset), it can hardly hurt the averages of the bottom ten.