Continuing with other recent MLB Draft Guide pieces it’s time to look at another grouping advanced statistics. Ground ball, fly ball, and line drive rates are another way to classify or identify pitchers. You’ll often hear experts say, “he’s a ground ball pitcher” or “this guy is more of a fly ball pitcher.” Don’t overthink it. The terms are pretty straight forward, but hopefully this piece can shed some light on what comes with being a ground ball or fly ball pitcher.
Ground Ball Rate
So ground ball, fly ball, and line drive percentages will always equal 100%. Makes sense, right? A typical “ground ball” pitcher will have roughly a 50% ground ball rate. Now just use that as a general rule of thumb, because there were only ten pitchers in the league last year to have at least a 50% ground ball rate. There were still 33 pitchers that had a 45% ground ball rate that can still be considered “ground ball pitchers.”
Typically a ground ball pitcher is better at keeping the ball in the park, but they may be prone to giving up more hits. Here were the top ten pitchers for ground ball rate in 2017:
- Marcus Stroman: 62.1%
- Luis Perdomo: 61.8%
- Clayton Richard: 59.2%
- Mike Leake: 53.7%
- Sonny Gray: 52.8%
- Carlos Martinez: 51.3%
- Luis Severino: 50.6%
- Patrick Corbin: 50.4%
- Jimmy Nelson 50.3%
- Zach Davies 50.2%
There are some good names up there in that list. Most of them are easily worth drafting, while others certainly warrant consideration as a streamer. But when a ground ball is in play there’s a chance it goes for a hit. To clarify, ground balls are more likely to go for hits than fly balls. Because of this six pitchers listed above (Richard, Perdomo, Leake, Corbin, Davies, and Stroman) are also in the top 20 in highest opponent batting average. But ground balls are also safer because rarely does a ground ball result in an extra base hit. Ground ball pitchers are also more likely to generate double plays in the event that a runner does get on base.
Now it’s not too surprising that six of the players listed above are also in the top 20 in highest home run to fly ball ratio. No pitcher is perfect and they’ll all give up home runs. But the players with lower fly ball rates are exposed to a higher HR/FB ratio because they don’t give up as many fly balls in general. This is something to consider if you play in a league where HR/FB ratio is a category in head-to-head leagues. Oddly enough the ground ball pitchers are the ones that could hurt you in that section.
Fly Ball Rate
Most “fly ball pitchers” will have a fly ball rate around 40%. In 2017 there were only twelve pitchers with at least a 40% fly ball rate. Those players are listed below:
- Marco Estrada: 50.3%
- Dylan Bundy: 47.2%
- Max Scherzer: 46.6%
- Dan Straily: 45.9%
- Jeremy Hellickson: 43.8%
- Justin Verlander 42.7%
- Ervin Santana: 42.5%
- Matt Moore: 41.9%
- Jason Hammel: 41.2%
- Chris Sale: 40.9%
- Jason Vargas: 40.4%
- Robbie Ray: 40.3%
Now only two of those players (Ray and Hellickson) appeared in the top 30 for pitchers with the highest HR/FB rates. This typically makes sense because while they give up more fly balls the percentage of which that leave the park is likely lower. And because fly balls traditionally result in outs more often than ground balls, fly ball pitchers will likely have a lower opponent batting average. Coincidentally enough only Moore, Vargas, and Hammel cracked the top 20 list of pitchers with the highest opponent batting averages.
Fly balls are a bit annoying though. Infield fly balls are categorized as fly balls, which is understandable but yet they’re also more difficult to predict. But at what point does a fly ball become a line drive or vice versa? There’s hardly a definitive distinction, but line drive rates are ultimately a death sentence for pitchers.
Line Drive Rate
Outside of home runs, line drives are a nightmare. Line drives typically result in hits, extra base hits, and runs. They are, however, somewhat misleading. As previously mentioned in the fly ball portion of this piece there’s no clear indication of the difference between and fly ball and a line drive. But also take a look at the list of players with the ten highest line drive rates in 2017:
- Martin Perez: 24.8%
- Justin Verlander: 23.8%
- Ivan Nova: 23.4%
- Zach Davies: 22.6%
- Yu Darvish: 22.4%
- Jimmy Nelson 22.4%
- Kevin Gausman: 22.1%
- Jeff Samardzija: 22.1%
- Corey Kluber: 22.1%
- Alex Cobb/Chris Archer: 22.0%
Now a couple things stand out to me right off the bat. Justin Verlander, Corey Kluber, and Chris Archer are aces. Say what you will about Archer, but he’s an ace! Just because they gave up a higher-than-average line drive rate, fantasy players won’t be deterred from drafting these studs. Kluber, in his career, does have a line drive rate of roughly 22% so last year he was right on par with his average. But at the same time he has 10+ strikeout potential each time he goes out there with a career 3.13 ERA. So you’ll easily take that risk for a guy who gives up a line drive one out of every five times an opposing hitter makes contact.
The other thing that’ll grab your attention is that Zach Davies and Jimmy Nelson BOTH ended up on this list. Want to know what else they have in common? Refer back to the list for highest ground ball rates. They both cracked that list. So how could players that were ground ball pitchers crack the highest rates for ground ball pitchers AND the highest line drive rates? The answer could be twofold. First take into consideration the ballpark they play in. Miller Park is notorious for being a hitter’s park. Consider the possibility that there’s a chance they succumb to being victims of their own home environment. Another factor worth considering is sample size. It is always worth looking at a pitcher’s career batted ball rates instead of just one year. Kluber’s line drive rate was roughly on par with his career numbers. But look at Zach Davies. Over his three years in Milwaukee his ground ball rate has ranged from 57.6% to 45.5% to last year’s 50.2%.
As with any advanced statistic don’t just take the number at face value. Try and figure out why the numbers appear the way they do. If a pitcher’s career numbers suggest he’s a ground ball pitcher then you can safely assume so. If a guy’s numbers fluctuate try and examine his past seasons and break it down. Was he playing in a new stadium? Was he coming off injury? Is the velocity dropping? Was he working more pitches into his repertoire? Ground ball rates and fly ball rates are useful in labeling a pitcher as such. But rarely will you refer to a pitcher as a line drive pitcher. If that were the case fantasy players would often overlook names like Justin Verlander, Corey Kluber, Chris Archer, Jacob deGrom, Jake Arrieta, Jon Lester, and Chris Sale. All those players had a line drive rate over 20%. You’ll need heavy and consistent doses of luck if you avoid drafting those guys in your league because of a higher than average line drive rate.