|Eric Byrnes has a reputation of being a first pitch fastball hitter, but how does he stack up with the rest of the league? (Icon/SMI)|
You often hear a baseball commentator say a hitter is a first pitch fastball hitter. This usually means that he goes up to the plate looking for a fastball on the first pitch and he is likely to swing at it if he gets it. Eric Byrnes is a great example of a player with this reputation. If you have watched a Diamondbacks game in the past couple of seasons, you have likely heard some version of this about Byrnes.
The problem is that such comments aren’t very quantitative. How much does Byrnes swing at first pitch fastballs? How picky is he about where the pitch is located? How successful is he when he does swing? And, in addition to the raw numbers, we would like to be able to compare them to league averages so we really can say if he is a first pitch fastball hitter compared to others. Despite all the splits information for players out on the web, statistics like this aren’t available because you first need to identify the fastballs. Luckily for us, with some help from PITCHf/x identifying first pitch fastballs is rather easy. From that sample we can quantify who the first pitch fastball hitters really are.
For this study I looked at every hitter who had at least 100 plate appearances in which PITCHf/x was tracking pitches. I put the cutoff at 100 because I wanted a reasonable number of first pitch fastballs for each player and I wanted a large enough sample to ensure teams would have a decent scouting report on the hitter so I could look at pitcher response. This left me with 437 players in my sample.
I then used my pitch classification algorithm to identify if the first pitch was a fastball (two- or four-seamed) and I used my strike zone tool from last week to determine if the pitch was a strike by the MLB-defined strike zone. I now have enough data to calculate league averages for variables like first pitch fastball percent and how often a player swung at a first pitch fastball out of the strike zone.
While the mean is nice, these data also fit very well to a Normal (Gaussian) Distribution, so calculating the standard deviation is also very useful. I can then not only report the raw data for each player, but also how far he is from the mean. For example, if I say that a hitter has been thrown one standard deviation more first pitch fastballs, that means 84 percent of major league hitters saw fewer first pitch fastballs than he did. If you aren’t familiar with how these standard deviations work here is a good description.
We can now go metric by metric and look at the league average and the 10 highest and lowest players for that metric. Starting with percentage of first pitch fastballs a batter sees, which has a mean of 67.2 percent and a standard deviation of 6.8 percent, on any count the chance of a hitter getting a fastball is about 60 percent, so the first pitch is slightly a fastball count.
The players on the list for the highest first pitch fastball percentage are players you might expect to be there: mostly weak hitting middle infielders and catchers (a few other catchers just missed the cut) with little power. Pitchers aren’t scared of giving these guys a cookie because they aren’t likely to do much with it anyway, so the pitcher might as well try to get the at-bat over with as soon as possible.
On the other hand, the players with the lowest first pitch fastball percentage are a mix of some feared hitters (Dan Uggla just missed the cut) and some players with a reputation of swinging at just about anything. Players like Hunter Pence and Corey Hart rarely walk and generally go to the plate looking for something to hit. It doesn’t make sense to give in to these guys, especially early in the count.
Next is percentage of first pitch fastballs thrown inside the MLB-defined strike zone. The mean here was 49.2 with a standard deviation of 5.2. That mean was much lower than I expected, since we all know how important getting strike one is. Here are the highest and lowest strike percentages.
Again, the players with the highest strike percentage are the guys you would expect. None of these are dangerous with the bat, so the pitcher is trying to get the ball over and get the at-bat done as quickly as possible. The lowest strike percentage list is loaded with some big names and power hitters. Some are known as free swingers, so why throw them a strike if you don’t have to, and that starts with the first pitch of the at-bat. It is interesting to see Josh Hamilton on the list. Despite a fabulous 2008, Hamilton swung at more than his fair share of balls out of the strike zone. It didn’t seem to bother him, but if that continues, look for pitchers to throw him fewer and strikes.
When you think of first pitch fastball hitters, though, you think of guys who swing the bat when they get what they are looking for. This is best represented by the player’s swing percentage at first pitch fastballs regardless of whether the pitch is a strike. The league average here is 37.6 percent and the standard deviation is a whopping 11.0. That means that there is huge variation among hitters in this case.
Most of the players on the hack-tastic list are guys who have no business swinging at so many first pitches. Joey Gathright, for instance, is a leadoff man who should be working the count and getting on base to use his tremendous speed. Most of the other players don’t have enough power to justify such free swinging. Wily Mo Pena had just a terrible year in ’08, and this might be one reason. I have no idea what his first pitch fastball swing percentage was in previous years, but last year it was way too high and resulted in many easy outs or falling behind in the count.
On the flip side, the most patient hitters are mostly players you probably know. Most of these players are older and have a good eye at the plate; not swinging at the first pitch helps get them in a good hitter’s count. Luis Castillo, though, is a bit of an exception. Pitchers are throwing him a tremendous amount of first pitch fastballs and he is not swinging at them. The word is out that Castillo will be taking on the opening pitch, so pitchers are throwing the fastball to get strike one on him. While Castillo is a very good two-strike hitter, getting into a hole right away was a real problem for him last year and contributed to his poor performance.
We can then break things up even further to look at how often players will swing at pitches inside or outside the MLB-defined strike zone, starting with swing percentage on first pitch fastballs inside the strike zone. The mean is 58.6 with an astronomical 17.2 standard deviation. This means that a lot of hitters will be swinging almost every time, but a lot hardly ever will be swinging.
Most of the players who rarely swing at these strikes were the same ones who were hardly swinging overall. This makes a lot of sense: If a player is rather choosy at the plate overall, he is not likely to be swinging at a lot of balls. On the other hand, we have a relatively fresh list of players who are swinging almost every time at a first pitch fastball over the plate. These hitters very likely are coming up thinking first pitch fastball. When they get one in the zone, they are going to take their hacks. Several of these players are big power guys as well, so if you are a pitcher you don’t want to be giving them exactly what they are looking for.
What about pitches outside the strike zone? Who is swinging anyway when it is a first pitch fastball and who is laying off? The league average here is 17.6 percent with a standard deviation of 8.5 percent.
Do not, under any circumstances, throw any of the players on the top list a first pitch fastball in the strike zone. There simply isn’t any need to because they are more than happy to go outside the zone and swing at any fastball. The fact that Vladimir Guerrero and Victor Martinez show up here is not too surprising. They have had very good careers despite swinging at some poor pitches. They are the exceptions, rather than the rule, though. If you swing at poor pitches it will catch up to you at some point and may have caught up to these two as well. Again, the players who don’t swing much overall don’t swing much at balls.
Okay, now we know who is swinging or not swinging at a first pitch fastball, but who is getting the best results? We can look at batting average and slugging percentage for balls in play to see who is doing the most (and least) with the first pitch fastballs they see. Warning: almost all of these players have a really small sample size. League average here was a .326 batting average with a standard deviation of 0.105 and a slugging percentage of 0.518 with a standard deviation of 0.214.
On the plus side, rookie of the year catcher Geovany Soto saw the fewest first pitch fastballs of any player in the study, but when he did get one, he knew what to do with it. Some young players like Hanley Ramirez and Jarrod Saltalamacchia showed they were strong fastball hitters and the resurgent Russell Branyan burst out with a series of home runs after being called up from Triple-A. Here is a hint to pitchers for next season: The mussel likes fastballs over the plate and he can hit them very far.
On the down side, we have a list of players who struggled mightily last year. If you aren’t hitting the fastball, there is a good chance you just aren’t hitting, and that certainly was true of the players on this list. I keep waiting for Rickie Weeks to bust out and live up to all that potential, but it sure looks like he has a long way to go here. Weeks is supposed to be a fastball hitter who has to slow his bat with a wiggle to stay on the breaking pitches. Maybe Weeks would be better served to scrap the wiggle altogether and just concentrate on hitting the fastball.
There are a million different things that could be done with these data; I have just scratched the surface. I get a lot of e-mails from people telling me that they like my work and wish they could do some baseball statistical research but don’t have the time or math background to do so. So I am going to make all of these data on first pitch fastballs public for anyone to use to get started.
The data are in a simple .CSV file, so any spreadsheet program should be able to open it easily and the column headings are at the top. If you want to use it to do a write-up on your favorite player (for instance, Eric Byrnes) or team on your favorite blog, just please put a link back to this page somewhere in the post.
If you have questions, my e-mail is below and I’d be more than happy to help get you started.