Special Report: What's Causing College Baseball's Record-Breaking Home Run Surge

Image credit: Jacob Snow/Icon Sportswire via Getty Images

Editor’s Note: The story has been updated to reflect the final record breaking home run numbers.

For the third time in the past 30 years, home run rates are skyrocketing around college baseball. And for the third time in the past 30 years, it likely means that something is happening with the equipment.

In 2023, teams averaged 1.13 home runs per game, which set the all-time NCAA record. That smashed the previous all-time Division I record of 1.08 home runs per game, set in 1998 at the peak of the “drop 5” era of metal bats.

That leads to the simplest of questions: Why?

When the home run rate soared in the late 1990s, and again in the late 2000s, there were those who said it was because of improved training and player development—and the rise of steroid use—but then the equipment changed and the home run rate quickly receded.

The last significant rules-based equipment change came in 2015, when the seams on baseballs were reduced to try to bring home runs back into the game. In 2014, just two players in college baseball topped 20 home runs. Just 10 teams hit at least 50. That year, teams averaged 0.39 home runs per game.

This year, 25 individual players were averaging 0.39 home runs per game or more, and 25 teams have hit 100 or more home runs. There are a multitude of reasons for this. But we’re going to look at the three most frequently mentioned reasons for the home run surge and examine the logic behind them.

1. It’s the ball.

Many believe that the baseballs used in 2023 are “hotter” than those used in past years. Multiple coaches said that, anecdotally, they believe the baseballs are a key part of the home run surge.

If the drag of the baseball is just a little lower—something that can easily stay within the allowed parameters for a legal baseball—it would lead to extra distance on fly balls.

The Sports Science Laboratory at Washington State is in charge of doing all the bat testing to certify BBCOR bats for the NCAA. But they also have done testing on MLB baseballs. And they found that it doesn’t take much of a change to affect home run rates.

“What was found there was really small, consistent changes in the average seam height. A small but consistent amount led to an increase in home runs,” Sport Science Laboratory assistant director Nick Smith said.

As we have seen in Major League Baseball, the tolerance range for baseballs is wide enough that balls that perform quite differently can still fall within the range of specifications for a legal baseball. There has been no testing to fully flesh out this theory, but it’s one brought up by multiple coaches.

2. The bats have gotten better.

Some coaches said they believed that all the bat companies have figured out ways to legally improve the bats within BBCOR standards.

This is a little trickier to support then the theory about hotter baseballs.

In the late 2000s, the BESR (ball exit speed ratio) era of bat-testing came to an end because teams discovered that some of the composite bats started to perform dramatically better as they aged.

Composite bats as a general rule become higher performing as they age. The resins between the layers of fibers loosen. Once that happens, the walls of the bat will deform more at ball contact than they did when the bat was new. That leads to a better contact patch between bat and ball and a larger trampoline effect as the wall of the bat returns to its original form.

In the last few years of the 2000s, players and teams discovered that for some models, old bats would perform vastly better than new bats. That played a large part in the home run surge in 2008 and 2009, which led to the end of the BESR bat era.

Home run rates skyrocketed from 0.68 per game in 2007 to 0.96 in 2009 and 0.94 in 2010 as more and more teams began to use rolled bats. When the BBCOR (bat-ball coefficient of restitution) standard was adopted in 2011, the home run rate immediately dipped to 0.52 per game.

So maybe bat manufacturers have gotten better at producing higher-performing bats that remain within the BBCOR standards?

It’s possible that sweet spots are larger and better aligned with a hitter’s tendencies now than it was when BBCOR bats were first introduced, but according to Smith, the BBCOR bats have been performing very near the limit of how well they can legally perform almost from the inception of the standard in 2011.

Washington State’s lab testing involves firing a baseball at a bat that is held in a manner to closely replicate a true bat-to-ball contact. The test is designed to ensure that no wood bat will ever fail to meet the test parameters, so it’s a rather conservative approach to making sure that current metal/composite bats do not significantly exceed the performance of the same hitter using a wood bat.

“The limit is pretty low to be wood-like performance,” Smith said. “What we have seen with BBCOR, manufacturers are making bats that are right up against the limit. What they are doing now is making the sweet spot bigger and maybe aligning those pieces better.

“But the BBCOR number we report, it has been close to the limit (since the beginning).”

You won’t see many fresh bats in a college baseball game. The BBCOR bats, like BESR bats before them, perform better once they have been used a lot. But unlike BESR bats, BBCOR bats have been specifically designed to not have the same massive performance changes as they age.

Washington State’s lab tests each and every bat it certifies to destruction. They do not stop testing just because the bat no longer passes the compression test, which would get a bat thrown out as non-compliant. If a bat exceeds the BBCOR performance standards at any point before it cracks or otherwise breaks, it is a non-compliant bat.

“The way we have implemented BBCOR, we will measure the barrel compression. But it’s not used as a limiting factor. We don’t stop testing if it drops below the (compression) level for baseball,” Smith said. “We test the bat until it physically breaks.”

3. Cheating.

It’s impossible to say exactly how much cheating is driving the surge in home runs, but numerous players, coaches and other officials in college baseball said they are confident that it is playing a significant role.

Multiple people told Baseball America that they know that some college players are swinging illegal bats that perform far beyond BBCOR standards.

And that’s a problem because illegally tampered bats create a potential safety issue for players, umpires and coaches.

The injury risk to pitchers and other infielders, as well as base coaches and umpires, is amplified the harder balls are hit. At the major league level, two pitchers this spring have already suffered skull fractures when hit by comebackers.

This risk to player safety is actually what led to the first attempts to tone down college bats in the late 1990s. It was the fear that college baseball would lose insurance liability coverage that forced the change.

Insurance companies began to refuse to insure college baseball teams because of concerns about the dangers of how hard balls were being hit. Early in the 1999 season, some teams had to use wood bats in games because they were unable to get any insurance coverage to hit with metal. At the time, using the then-current testing, BA reported where wood bats produced a 93 mph exit velocity in testing, some of the bats in use in college baseball were producing 113 mph exit velocities in the same test.

“First is the fear of litigation,” said then-NCAA rules committee chairman Bill Rowe to BA about why the bat regulations were changing for 1999. “We didn’t want to have a player get hurt or killed and have the NCAA sued on this.

“Second, we just had a lot of people who watch college baseball and asked how long this kind of offense can go on.

“Third, we needed to do something to restore the integrity of the game. We felt in part that with all the high scores, the balance had been lost.”

Now, hitters are once again matching those home run numbers of the late 1990s, and producing exit velocities that are rarely seen in the major leagues.

It’s very difficult to filter out misreads on exit velocity measurements from real top-end exit velocities in college ball, but even after removing the most likely misreads—which include a significant number of exit velocities above 120 mph—at least seven Division I players have posted exit velocities of 117 or higher this year, and five have topped 118. More than 50 have had a 114 mph exit velocity or higher. In the major leagues, 39 players have hit a ball 114 mph or harder this eason.

“The performance of both metal and composite bats is something that the NCAA’s baseball research panel, as well as the certification at the sports science laboratory at Washington State University, are consistently and constantly looking at, ensuring we have safe equipment standards for manufacturers to meet,” said Ben Brownlee, NCAA assistant director of championships and alliances

“The emphasis there is that manufacturers have a standard that they have to meet. If they start to not meet that standard or exceed that standard, we have other mechanisms that we have to look at to take action.”

The current bat-testing rules are supposed to prevent illegal bats from getting into games, something that wasn’t even part of pre-game preparations a decade ago. As multiple players, coaches and officials explained to BA, the current system of bat testing has many loopholes that would allow a player to sneak an illegal bat into play, and the current system has very few penalties to discourage them from doing so.

As of now, the rule book does not try to spell out an attempt to make a distinction between tampered bats and broken bats. The NCAA rule book covers how to conduct pregame testing, and the equipment rules cover the use of an illegal bat.

“If something is obvious that a bat has been altered, I don’t want to say the language in the rule has been written so that it can be accounted for, but if a bat has been altered it’s no longer a legal bat,” Brownlee said.
“There has to be signs of tampering. There would have to be a gap between the end cap and the top of the barrel . . . If it appears the end cap has had something done to it, the taper area has had something done to it—those are reasonable signs that a bat has been altered, and we can question that bat.”

Unlike hitters, if a pitcher is discovered to have used a foreign substance, they are ejected from the game and given a four-game suspension. A hitter using an illegal bat faces no such threat of ejection or suspension. There is no significant penalty to prevent players from trying to get around the rule.

If a player manages to place one of the tamper-proof stickers onto an illegal bat, there is almost no concern that it will be determined to be illegal. Once a series begins in most conferences, there are no rules or mechanisms for a bat to be further tested to determine if it’s non-compliant. The umpires are simply told to check to make sure each bat has the sticker.

The easiest way for a player to slip a hotter, non-compliant bat into play is to carefully remove the sticker from a legal bat, and then place it on the better-performing, non-compliant bat.

While the stickers are designed to resist being removed, putting pine tar or other substances on the bat under the sticker apparently helps aid removal. Other sources say heating the stickers makes it easier to remove them.

All it takes is a simple Google search to discover a wide array of companies that are happy to sell players a wide selection of tampered bats. They will go to lengths to make sure that the tampered bat looks identical to a legal bat. They helpfully explain in their frequently asked questions section that their bats are indistinguishable from a legal bat from a visual perspective, though some sites do say that the sound of the ball coming off the bat may be different.

The biggest performance gains come from removing metal from the inside of the bat’s walls in a lathe. The shaving thins the walls of the bat, creating a more flexible wall that provides better exit velocity and distance than a stock bat. One company providing bat shaving services says that it will add 7.5 mph in exit velocity on average.

For some bats, it involves removing an inner sleeve inside the bat that was installed to ensure the bat didn’t gain too much performance as it aged. The sleeve prevents the outer wall from flexing too much.

The sites that sell the bats note that they should only be used for home run derbies or to develop confidence in practice. But they rely on the purchaser to decide how to use the bat. And the Websites point out how their bats looks identical to an untampered and legal BBCOR bat.

One of the bat-shaving websites posts a disclaimer on its purchase page: “This high performance bat is capable of producing batted ball speeds that present a risk of serious injury or death to players, coaches, umpires or spectators.”

Such bats will fail compression testing, and if the end cap is removed, it is obvious that they have been shaved. In reality, if a hitter slips a sticker onto a well-done tampered bat, there’s little chance that the bat will ever be put in a compression tester that would prove its illegality. And without a teardown of the bat, even if it was ever tested, failing the test could be explained away as the bat must have broken at some point.

No one can say how exactly pervasive bat tampering is, but multiple coaches and players agreed that it is occurring and is playing a role in the home run surge.

And as multiple people in college baseball explained, the rules do little to dissuade players from cheating, because the reward far outweighs the risk. Not only can it help a team win more games, but the players themselves can vastly improve their chances of being drafted or drafted much higher.

MLB teams look at a player’s 90th percentile exit velocities as one of the most useful indicators of a prospective draftee’s power and a key factor in many draft models. If a batter uses an illegal bat to generate that power, he may have cashed his bonus check long before the team discovers that power disappeared as soon as he started hitting with wood.

It also creates an uneven playing field, and the increased exit velocities put pitchers, infielders and umpires at risk of serious injury.

But until the rules are tweaked to make discovering tampered bats possible and to make the penalties for such tampering much more severe, players and coaches expect that this form of cheating will continue.

Teddy Cahill and Peter Flaherty contributed to this story.