The Importance of Hard-Hit Percentage

In some ways, baseball is a simple game. For a hitter, it boils down to: see ball, swing at ball, hit ball hard, jog around bases (the Frankenstein approach). Of course, it’s not really that simple and there are many other variables involved. Still, a simple goal for a hitter would be to hit the ball hard as often as possible. With that in mind, I thought I’d investigate what happens when a batter hits the ball hard on a regular basis.

I took all players with 150 or more plate appearances so far in 2015. All data in this article is through June 14. Using players with more than 150 plate appearances gave me 236 players.

To start off, I looked at the correlation between the old-school statistic of batting average with hard, medium, and soft hit percentage. You may think that players who hit the ball hard more often would have higher batting averages. This is true. The correlation between batting average and hard hit percentage for these 236 players was .18. For both medium and soft hit percentage, the correlation was negative. The more often you hit the ball hard, the higher your batting average. The more often you hit the ball medium or soft, the lower your batting average.

Here is a table that shows the correlation for other metrics:

The statistic that correlates most with hard-hit percentage (Hard%) is Isolated Slugging (ISO), with a correlation of .73. Hitting the ball hard more often leads to getting extra-base hits more often. The top three metrics in the table—ISO, HR/FB, and SLG—are all measures of power and correlate quite nicely with Hard%. The two measures of overall hitting production—wRC+ and wOBA—also score high on this chart.

Both strikeout rate and walk rate correlate positively with Hard%. When you swing hard, you are more likely hit the ball hard and also more likely to miss, so hitters who have a higher Hard% also have higher strikeout rates, in general. Hitting the ball hard also correlates with walking more often. Perhaps pitchers a more careful to hitters who can beat them with one swing of the bat.

Hard% has a positive correlation (0.36) with fly-ball percentage, no correlation with line-drive percentage, and a negative correlation with groundball percentage.

With all of that in mind, I decided to separate hitters into groups based on hard-hit percentage and compare their composite batting lines. Consider the charts below. There’s a great deal of information here, but if you go down the column as Hard% goes down, you can see the effect on other statistics.

The group of hitters who have a hard-hit percentage of 35% or higher have combined to hit .276/.356/.491. Their .276 batting average is 9 points higher than the next-highest group, their OBP is 22 points higher, and their slugging percentage is 49 points higher. They have a .215 ISO, a solid 10.2% walk rate, and the best HR/FB rate, at 17.5%.

As the hard-hit percentage goes down, the other numbers go down also. By the time you get to the bottom group, those with Hard% below 23%, the composite batting line is .252/.303/.332, with an ISO of .080 and a HR/FB rate of 3.4%. This group strikes out less often than any other group, has the highest rate of soft-hit balls, and the lowest rate of fly balls. These are your typical light-hitting shortstops (Alcides Escobar, Elvis Andrus) and speedy outfielders (Billy Burns, Sam Fuld).

The three wRC+ columns show the number of hitters with a wRC+ at 100 or higher, the number below 100, and the percentage of above-average hitters in each group. For example, 86% of the hitters with Hard% above 35% have been above-average hitters this year, while just 19% of the hitters with Hard% below 23% have been above-average. If you’re not hitting the ball hard with some frequency, you are unlikely to be productive. The break-even point where half the players are above average hitters and half are below is in the range of 27% to 28% hard hit balls.

Let’s take a closer look at these groups.

Diamond Group (35% and higher Hard%)


.276/.356/.491, .321 BABIP

.215 ISO, 17.5% HR/FB

10.2% BB%, 22.3% K%

WAR/600 PA: 4.0

wRC+ >100: 43 players (86%)

wRC+ <100:   7 players (14%)


Best Hitter: Bryce Harper, 216 wRC+

Median Hitter: George Springer, 131 wRC+

Worst Hitter: Matt Kemp, 78 wRC+


  • Top five hitters in this group, by wRC+: Bryce Harper, Paul Goldschmidt, Miguel Cabrera, Mike Trout, Anthony Rizzo.
  • Middle five hitters in this group, by wRC+: Andrew McCutchen, Jose Abreu, George Springer, Adam Lind, Seth Smith.
  • Bottom five hitters in this group, by wRC+: Mark Trumbo, Will Middlebrooks, Matt Adams, Steve Pearce, Matt Kemp.
  • Bryce Harper is the top performing player in this group, hitting .333/.469/.721 with a Hard% of 40.4% and a 216 wRC+. He’s the Hope Diamond of Major League Baseball right now.
  • Giancarlo Stanton has the highest Hard%, at 51%. Stanton’s .341 ISO is second in baseball to Harper’s .388. Stanton’s Hard% is 5% higher than the next-highest player in baseball, Brandon Belt.
  • Nine of the top ten hitters in baseball by wRC+ are in this group (Nelson Cruz missed the cut with a Hard% of 32.9%.
  • The seven below-average performers with a 35% or higher Hard% are Jorge Soler (96 wRC+), Jay Bruce (96 wRC+), Mark Trumbo (93 wRC+), Will Middlebrooks (80 wRC+), Matt Adams (79 wRC+), Steve Pearce (79 wRC+), and the enigmatic Matt Kemp (78 wRC+) bringing up the rear. These players are hitting the ball hard at a high rate but have still been below average hitters.
  • Speaking of Kemp, what is up with this guy? After a bounce-back year in 2014, when he hit 25 home runs in 599 plate appearances, Kemp has just two homers so far in 274 plate appearances. He’s the Robinson Cano of the National League. His 35.4% Hard% isn’t bad, but it’s not as high as last year’s 40.3%. He also pulled the ball more often last year (43.8%) and his ground ball rate is at a career high (48.7%, career rate is 41.9%). He is struggling big time on fastballs after crushing fastballs in 2014. It’s been an ugly start to the year for Kemp, just ask Bud Black.
  • Two players in this group who are very close to a 100 wRC+ are Ryan Howard (100 wRC+ and Pedro Alvarez (104 wRC+). They both have been terrible against left-handed pitchers, having struck out at least 30% of the time against lefties. Also, when they do make contact against southpaws, they aren’t making good contact, with identical 25% Hard% versus lefties.


Quartz Group (31% to 35% Hard%)


.265/.334/.442, .300 BABIP

.177 ISO, 14.1% HR/FB

8.6% BB%, 19.4% K%

WAR/600 PA: 2.9

wRC+ >100: 39 players (75%)

wRC+ <100: 13 players (25%)


Best Hitter: Nelson Cruz, 175 wRC+

Median Hitter: Evan Longoria, 115 wRC+

Worst Hitter: Christian Yelich, 68 wRC+


  • Top five hitters in this group, by wRC+: Nelson Cruz, Mark Teixeira, Andre Ethier, Albert Pujols, Stephen Vogt.
  • Middle five hitters in this group, by wRC+: Danny Espinosa, Carlos Santana, Evan Longoria, Khris Davis, Mark Canha.
  • Bottom five hitters in this group, by wRC+: Justin Maxwell, Luis Valbuena, Robinson Cano, Michael Taylor, Christian Yelich.
  • The magic pixie dust that Nelson Cruz was sprinkled with in April (206 wRC+) and May (188 wRC+) seems to have worn off in June (78 wRC+). His ISO has dropped from .402 to .262 to .000 by month (although he has continued to be fortunate on balls in play with a .393 BABIP in June). He’s also seen a big drop in the percentage of hard hit balls, from 40.6% in April to 30.1% in May to 21.4% this month. This has coincided with a drop in fly ball rate, from 55.1% to 27.4% to 21.4%. Cruz was never going to keep up his torrid early-season pace but he’s also not as bad as he’s looked recently.
  • The player at the bottom of this group, Christian Yelich, has an above average Hard% of 34.2%. Unfortunately, his sky-high ground ball rate (69.1%) and miniscule fly ball rate (15.4%) mean those hard hit balls are not providing much production (68 wRC+).
  • Another player in this group, Luis Valbuena, is having a very peculiar season. He’s hitting the ball hard (31.5% Hard%) and hitting a ton of fly balls (50.3%), which has resulted in 14 home runs in just 234 plate appearances. His career high was set last year when he hit 16 dingers in 547 plate appearances. Valbuena has seen his fly ball rate increase in each of the last three seasons from 35.4% in 2012 to his current rate of just over 50%. That all sounds very good until you look at his ugly .185/.256/.412 batting line, good for an 86 wRC+. With all of those balls flying over the wall for home runs, Valbuena has a .169 BABIP. It’s surprising that a player could hit 14 home runs in 234 plate appearances and be a below-average hitter but Valbuena is doing it.


Apatite Group (28% to 31% Hard%)


.267/.325/.417, .307 BABIP

.150 ISO, 10.8% HR/FB

7.3% BB%, 18.4% K%

WAR/600 PA: 2.5

wRC+ >100: 30 players (60%)

wRC+ <100: 20 players (40%)


Best Hitter: Jason Kipnis, 160 wRC+

Median Hitter: Torii Hunter, 110 wRC+

Worst Hitter: Alexei Ramirez, 51 wRC+


  • Top five hitters in this group, by wRC+: Jason Kipnis, Josh Reddick, Justin Turner, Russell Martin, Brian Dozier.
  • Middle five hitters in this group, by wRC+: Edwin Encarnacion, Trevor Plouffe, Torii Hunter, Daniel Murphy, Brad Miller
  • Bottom five hitters in this group, by wRC+: Aaron Hill, Nick Castellanos, Ryan Zimmerman, Mike Zunino, Alexei Ramirez.
  • Jason Kipnis tops this group of players with a 160 wRC+, 50 points higher than the median player in this group. He’s having his best season. Looking at his numbers, he’s striking out less often than he ever has and has a .375 BABIP that is 68 points higher than his career mark. He’s also hitting fewer fly balls than ever (26.9% FB% compared to a career mark of 30.8%). He’s replaced those fly balls with line drives. His current Hard% almost exactly matches his career rate, but he’s done it in an interesting way. In three of his first four seasons, his Hard% was around 27% (2011, 2012, 2014). In 2013, his Hard% was 35.3%, which would put him up in the elite group (the Diamonds). That 2013 season was his best before this year’s revival. Kipnis is not going to OBP over .400 and likely won’t slug over .500, but he’s looking more like the 2013 version of himself than last year’s colossal disappointment. Maybe this is what a healthy Kipnis looks like.
  • The two players at the very bottom of this group in wRC+ are Mike Zunino and Alexei Ramirez. Zunino just strikes out way too much (36.7% K%). He has power (.159 ISO, 13.0% HR/FB) because he does hit the ball hard, but he doesn’t hit the ball hard often enough to be productive.
  • Alexei Ramirez is actually hitting the ball hard more often than he has in any season in his career. His current 28.4% Hard% is quite a bit higher than his career mark of 23.7%. His batted ball profile hasn’t changed, with a similar rate of line drives, ground balls, and fly balls. He does have the lowest BABIP of his career, at .256 (career mark is .293) and he’s walking at the lowest rate of his career, although he’s never been one to walk much.


Calcite Group (25% to 28% Hard%)


.262/.313/.378, .303 BABIP

.116 ISO, 7.4% HR/FB

6.3% BB%, 16.9% K%

WAR/600 PA: 1.8

wRC+ >100: 16 players (30%)

wRC+ <100: 37 players (70%)


Best Hitter: Mike Moustakas, 133 wRC+

Median Hitter: Jean Segura, 91 wRC+

Worst Hitter: Danny Santana, 42 wRC+


  • Top five hitters in this group, by wRC+: Mike Moustakas, Dustin Pedroia, Brandon Guyer, Cameron Maybin, Rajai Davis.
  • Middle five hitters in this group, by wRC+: Cory Spangenberg, Juan Uribe, Jean Segura, Martin Prado.
  • Bottom five hitters in this group, by wRC+: Dustin Ackley, Lonnie Chisenhall, Chris Owings, Jordy Mercer, Danny Santana.
  • The Bizarro World version of Mike Moustakas tops this group. This is the first time Moustakas has ever been an above average hitter in his major league career, but it doesn’t look like Hard% has much to do with it. His Hard% of 25.6% is right in line with most of his career and close to his career average (last year’s 31.7% is an outlier). The rest of his batted ball profile is quite different, from the lowest fly ball rate and highest ground ball rate of his career, to the direction he’s hitting the baseball. After never hitting the ball to the opposite field more than 22.7% of the time in a season, Moustakas’ 33.3% Oppo% this season is a career high. That may explain some of his elevated .346 BABIP (.270 career mark). He’s also striking out less frequently than he usually does (11.1% K% to 16.1% career mark). On the other hand, looking at his monthly splits throws up a big red flag. Moustakas went opposite field 39% of the time in April, 30.7% of the time in May, and is at 26.3% in June and has seen his wRC+ drop from 170 in April to 112 in May and June (aided by a .368 BABIP in June). Whatever changes he made in April don’t seem to be sticking, as his batted ball locations in June look much more like his career marks than they did in April. This Tiger may be reverting back to his original stripes. It seems strange that he would consciously make that change despite being so effective in April, so it could be that pitchers have adjusted and are pitching him differently.
  • Among this group of 53 players with Hard% between 23% and 28%, Salvador Perez has the most home runs, with ten. This is interesting because Perez has had much higher Hard% rates over the last three years, when his lowest mark was 29.8%. This year, he’s hit fewer hard hit balls but has the highest HR/FB of his career. That doesn’t seem like something that can continue going forward.


Talc Group (23% and below Hard%)


.252/.303/.332, .290 BABIP

.080 ISO, 3.4% HR/FB

6.4% BB%, 14.8% K%

WAR/600 PA: 1.1

wRC+ >100:   6 players (19%)

wRC+ <100: 25 players (81%)


Best Hitter: Nori Aoki, 131 wRC+

Median Hitter: Eric Sogard, 69 wRC+

Worst Hitter: Rene Rivera, 24 wRC+


  • Top five hitters in this group, by wRC+: Nori Aoki, Jacoby Ellsbury, Jose Iglesias, Billy Burns, Dee Gordon.
  • Middle five hitters in this group, by wRC+: Alcides Escobar, Elvis Andrus, Eric Sogard, Freddy Galvis, Jimmy Rollins.
  • Bottom five hitters in this group, by wRC+: Melky Cabrera, Chase Utley, Jose Ramirez, Omar Infante, Rene Rivera.
  • If you aren’t hitting the ball hard on a regular basis, you better find some holes. The top 12 hitters by wRC+ in this group have BABIPs at .311 or higher and the top five are significantly higher than that: Aoki–.344 BABIP, Ellsbury–.379, Iglesias–.367, Burns–.366, Gordon–.418.
  • On the other hand, the players at the bottom of this group in wRC+ are not only struggling to hit the ball hard but also struggling to get those balls to drop in for hits: Utley–.189 BABIP, Jose Ramirez–.205, Infante–.241, Rene Rivera–.198. Of course, this may not stop Infante from starting the All-Star game, but that’s a whole different topic.
  • These players don’t hit home runs, for the most part. Of this group of 31 players, just two have more than four home runs and 25 of the 31 have 0 to 2 home runs.
  • Stephen Drew leads this group with 9 home runs, despite a Hard% of 20.4%. His career rate is 30.6% and he had a 38.8% Hard% in 2013, the last year he was an above average hitter (109 wRC+). In that 2013 season, Drew had a fly ball rate of 41.6%. Drew then went unsigned prior to the 2014 season and missed spring training and the first two months of the year before joining the Red Sox in early June. He appears to be a very different hitter than he’d been before. His Hard% has been 23.2% and 20.1% in 2014 and 2015 after regularly being around 30% in previous seasons. He’s also greatly increased his rate of fly balls, from a consistent 40-42% from 2009 to 2013 to around 50% the last two seasons. Along with the increase in fly balls is an increase in the number of balls he pulls. His career rate is 41.2%. Over the last two seasons he’s pulled the ball over 50% of the time. Along with these changes in batted ball profile, Drew has a .182 BABIP since joining the Red Sox in early June of 2014. It’s hard to believe that missing a half season could result in such a dramatic change in a player’s batted ball profile, but it may have happened to Drew and it’s not a good thing for him.
  • Jimmy Rollins is the other hitter in this group with more than four homers. He currently has seven. His HR/FB rate is 10.6%, which would be the highest he’s had since 2007. Unfortunately, that’s about all he’s done well on offense, as he is hitting .199/.260/.336 (.265 wOBA, 68 wRC+).


Bobby Mueller has been a Pittsburgh Pirates fan as far back as the 1979 World Series Championship team ("We R Fam-A-Lee!"). He suffered through the 1980s, then got a reprieve in the early 1990s, only to be crushed by Francisco Cabrera in 1992. After a 20-year stretch of losing seasons, things are looking up for Bobby’s Pirates. His blog can be found at and he tweets at

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8 years ago

Good stuff