Explaining Why the Bunt Is Foolish in Today's MLB

Over the years, the bunt has been attacked again and again...and again for good measure.

Yet you still see bunts in Major League Baseball games. In fact, league batted ball data over at FanGraphs shows that the percentage of bunt base hits has been up the last couple of years, and goodness knows managers still keep the sacrifice bunt in their toolboxes. 

So no, the bunt isn't dead yet. It hasn't gone the way of the Tyrannosaurus Rex or CC Sabathia's fastball velocity just yet.

But make no mistake about it: The bunt is still out of place in today's game. There's a time and a place for a good bunt, but it's a dated play that is still used more often than it should be.

If you're up for yet another assault on the bunt, pull up a chair and allow me to explain what the deal is.

The League Gets It

We'll get to why hitters trying to bunt for base hits isn't such a great idea soon enough, but first we should discuss the sacrifice bunt and its place in baseball today.

That's best described with the phrase "on thin ice." 

The following graph shows the number of sacrifice bunts per game by year since 1975, with the data coming courtesy of Baseball-Reference.com:

You can see that we're not looking at a straight downward trend, but the sacrifice bunt is certainly a rarity compared to its use in the late 1970s.

You can thank sabermetricians for this. Bill James and others began waging war on the sacrifice bunt years ago, and eventually sabermetric thinking took over front offices and has slowly trickled down onto the field.

It's going to take a while before the sac bunt is out of the league completely, of course. Particularly in the National League, where pitchers are still required to "hit." Until the designated hitter finds its way to the Senior Circuit, the sac bunt will avoid total extinction.

But for the most part, the sac bunt has fallen out of favor because teams are too smart to be so dumb. They know that the data says that giving up an out to advance a runner is a very bad idea.

That's something that Anthony Castrovince of MLB.com dove into earlier this year using Run Expectations data from Baseball Prospectus. The Run Expectation with a runner on first and nobody out is higher than it is when there's a runner on second and one out, the situation usually created by a sac bunt.

The trend holds when discussing Win Expectancies in late-inning situations, which is something that noted sabermetrician Tom Tango tackled back in 2002. The win expectancy for a home team trailing by one in the bottom of the ninth is higher with a runner on first and nobody out than it is with a runner on second and one out. And so on.

Maybe you've heard these arguments before, but they're always worth repeating. It's data like this that upholds the age-old sabermetric stance that outs are too precious to give away with sac bunts. 

It doesn't help that the league has gotten to be particularly bad when it comes to actually converting sac bunts. Here's a look at the success rate of sac bunts since 1975:

Again, we're not talking about a straight downward trend, but you can see that things started going south in the 1980s and got to be even tougher in the mid-2000s.

There's been a spike in successful sacrifice bunts this year, sure, but we're barely a quarter of the way through the season. Based on recent history, it's probably not going to hold.

It makes sense that the success rate of the sac bunt would be going down rather than up. Defenders should know how to defend the bunt better now than ever before, and there simply aren't that many offensive players who specialize in bunting anymore.

They've evolved.

How Hitters Have Changed

Regardless of what you believe about the proper timing for a bunt in terms of game situations, what we can all shake on is that bunts should always occur early in the count.

A bunt should be put down before a hitter has the count in his favor, otherwise he risks giving up on a potential walk. A bunt should certainly be put down before a hitter has two strikes on him, as a foul bunt means a strikeout and a spot in the skipper's doghouse.

And that's the thing about bunts and today's hitters. They don't like doing much of anything early in counts.

Take a look at the rise in the league average for pitches seen per plate appearance since 1988:

*It's important to note that such data doesn't go back any further in the past than 1988.

Working the count: It's not just for middle-of-the-order guys anymore.

It's fair to conclude that the downfall of the bunt has fed into this trend, as has another trend (rhymes with "mikeouts") that we'll be discussing soon. But the big contributor is the increased emphasis on pitch counts. Hitters want pitchers to escalate their pitch counts so they can take advantage of either A) a tired pitcher or B) middle relievers. 

So for today's hitters, bunting is counterintuitive. Bunts offer pitchers potentially easy outs, and they do them the favor of conserving their ammunition.

Another reason why the bunt doesn't make a whole lot of sense for today's hitters has to do with the fact that, collectively, they're more powerful.

The Steroid Era may be long gone, but the rate of home runs per game is still high relative to where it was in the late 1970s and most of the 1980s:

This is proof that pretty much everyone can hit for power these days. And since pretty much everyone can hit for power, why settle for a bunt when a homer could be in the cards? That's choosing to try for one run the hard way instead of trying for one run the easy way.

Then there's the elephant in the room. In a league where home runs are more easily hit, it doesn't make sense to play for one run in most situations. Other teams can hit homers too, and that means one-run deficits are easily overcome.

There are other reasons why the bunt doesn't belong in today's MLB, and they have to do with the guys at the top and bottom of the league's lineups.

The job of leadoff hitters is still the same today as it's ever been. They need to get on, get in scoring position and come home. The difference now is that they don't need as much help getting in scoring position, as leadoff men have become more powerful.

Here's a look at the slugging percentages posted by No. 1 hitters since 1975:

There are some peaks and valleys here, but generally what this graph shows is that leadoff slugging percentages have been higher lately. It's a little bit more clear if you consider the averages for the different time periods noted above:

• 1975-1979: .370
• 1980-1989: .375
• 1990-1999: .391
• 2000-2009: .407
• 2010-2013: .395

Leadoff men have become less powerful in the last three-plus years, but they're still more powerful than they were in the late 1970s, 1980s and 1990s.

As for bottom-of-the-order guys, non-pitcher 7-8-9 hitters have tended to be more productive in recent years. Here's a graph that shows their OPSs since 1975:

More peaks and valleys, but you can see that, even with the recent downturn in offense, bottom-of-the-order guys are still more productive now than they were in the late 1970s and most of the 1980s.

So to recap, hitters should be shying away from the bunt because they're more patient, it's not just the big boppers who can hit the ball hard, and because both leadoff men and bottom-of-the-order hitters have changed.

The short version is that lineups are deeper and tougher to get through than they used to be, so it doesn't make much sense for hitters to embrace a play that survived for so many years as the province of light-hitting types who needed the bunt to avoid being automatic outs.

But I suppose now's the time for me to acknowledge the glaring question: With offense on the decline the last couple years, why shouldn't the bunt be making a huge comeback?

We have to look at pitchers to answer that question.

How Pitchers Have Changed

For a long time, MLB was a hitters' league. Now it's a pitchers' league again, as evidenced by the fact that the league ERA has been in the low 4.00s or high 3.00s each year since 2010.

The easy conclusion to draw is that pitchers are more in control now than they've been in a long time. We'll discuss in a minute how that's true, but first we have to discuss how that's kinda-sorta-not-really true.

Consider this batted ball data, which comes from FanGraphs:

*Batted ball data only goes as far back as 2002.

All over the place, right?

That's the point. Balls in play are still unpredictable, and the only thing that can be called a trend in recent years is the steadiness of the league ground-ball percentage since 2010.

That's something that can be chalked up to the skill of pitchers. Most pitchers who pitch to contact are going to have the idea in mind to get ground balls. They're not likely to hurt, after all, as balls on the ground have a smaller likelihood of becoming extra-base hits.

However, ground balls aren't the worst thing in the world for hitters. Ground balls may have a small chance of becoming extra-base hits, but they generally have a greater chance of becoming base hits than fly balls do. 

Even in a day and age where infield shifts are all the rage, the league batting average on ground balls is staying relatively steady:

• 2008: .236
• 2009: .236
• 2010: .234
• 2011: .237
• 2012: .238
• 2013: .235

And this is relevant to the matter of bunts. Instead of trying to bunt for a base hit, it makes more sense for hitters to swing away. If they don't get a pitch to drive over the fence, they can always poke one through the infield for a base hit. 

Sacrifice bunts are an even worse idea against today's pitchers, as they have greatly increased their ability to render sac bunts moot.

How?

Simple: more strikeouts.

It's not much of a secret that the league's strikeout rate is going up. Everyone's written about it, from ESPN's Jayson Stark to CBS Sports' Scott Miller to yours truly. For a variety of reasons, pitchers are punching out hitters like never before. 

And they're not laying off when runners are in scoring position. This graph, using information pulled from FanGraphs, shows the league strikeout percentage (strikeouts/plate appearances) with men in scoring position since 2002:

The whole idea with getting a man into scoring position is to advance him further along with a ball in play, preferably a run-scoring base hit. Pitchers are making giving up an out to do so into a very dangerous game, as trading an out to put a runner on second can easily result in a wasted effort by way of a strikeout for out No. 2.

Thus, the familiar refrain: It's better to take your chances by swinging away.

Final Thoughts

I acknowledged way back when that there are times and places for a good bunt, and to that I hold.

Using pitchers to bunt runners over will have to do until they learn how to hit or are replaced by the DH. It's not the worst thing in the world for the home team to play for one run in a potential walk-off situation. Even a good squeeze play is OK now and again.

It's outside of these times and places that the bunt just doesn't fit in the modern game. Today's hitters don't need to bunt for base hits as much as hitters did in the old days, and we have both general statistics and the increased nastiness of pitchers to tell us that sac bunts are rarely a good idea.

The war on the bunt will come to an end eventually, but not before baseball catches up with the times.

Note: Stats courtesy of Baseball-Reference.com unless otherwise noted.

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