Why are home runs flying in Triple-A? Turns out, all baseballs are not created equal

For years, it was something of an open secret, talked about among true seamheads but largely obscured from public view: The baseball used in the major leagues is the hardest, most tightly wound and offensively explosive piece of equipment in the sport.

Thanks to the big-league baseball’s use at the Class AAA level for the first time this season, there is now growing statistical evidence – and ample anecdotal evidence – that the differences between the major league ball and others used in the professional ranks are more significant than imagined.

“To see the big league ball fly for the first time – it’s pretty mind-blowing,” says Tampa Bay Rays reliever Emilio Pagan, who has pitched at the Class AAA level each of the past three seasons. “Guys that had never seen it before, well, it’s hard to put into words how much farther the big league ball goes, because it’s spun tighter.

“The minor-league parks don’t have the third or fourth deck to knock down the wind – so it’s just going to go. You’re going to see some pretty unbelievable numbers.”

It’s already happening.

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The home run rate at the Class AAA level has leaped by nearly 50% – from 1.74 homers a game last year to 2.56 this year, even before the weather’s warmed up. Perhaps the only mechanism preventing a slew of Bondsian seasons on the farm will be promotions to the big leagues.

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Reds infielder Josh VanMeter slugged his way into a call-up to Cincinnati by cracking 13 home runs in 30 games, a 70-homer pace.

And someone say a prayer for pitchers in the Pacific Coast League, where high altitude and desert air were already big enough obstacles. Five players have already hit at least 10 homers in 30 or fewer games.

El Paso outfielder Jacob Scavuzzo has hit 10 homers in 15 games – a small but nonetheless absurd sample.

“Somebody in the PCL is going to hit 55, if they’re there all year,” says Rays first baseman Nate Lowe, who made his major league debut last week. “It’s that much of a difference.

“If you hit a ball flush, regardless of what kind of ball it is, it’s going to go. But the mishits with the balls now, even playing in Triple-A parks, is just crazy.”

Lowe’s perspective is valuable, in that he spent one month in Class AAA last year and a month there this season before getting promoted. The difference in balls year-to-year was palpable: Lowe’s Durham (N.C.) Bulls and the Charlotte Knights, the top White Sox affiliate, combined for 17 home runs in the first four games of the season.

So why turn Class AAA games into arena baseball, with still-developing pitchers tossing the same, lively (and possibly juiced?) ball as their big league brethren?

Believe it or not, it’s a significant courtesy to pitchers, particularly relievers and spot starters who shuttle frequently from the big club to the minors.

The difference in feel and movement between the major league and minor league ball is significant. The minor league ball has bigger, higher seams, and multiple pitchers told USA TODAY Sports a breaking pitch can drop into the strike zone using far less hand speed.

The major league ball is wound tighter, which produces greater carry. There’s also a risk-reward element for pitchers: Getting the ball to break requires greater effort, but the movement on all pitches can be enhanced.

“That change in ball is a little more of an issue than people realize,” says St. Louis lefty reliever Tyler Webb, who’s mixed brief stints at Class AAA with big league appearances for the Cardinals, Yankees, Brewers and Padres. “Now, it’s one ball, both ways, so it’s one less thing you can kind of eliminate from going up from Triple-A to the big leagues, which is ultimately a good thing.

“It might go a little farther down there - especially in the PCL – but it’s a good tradeoff to know what that ball’s going to do when you get called up.”

And what does that mean for Webb, who has stranded all seven runners he’s inherited this season, yet has yielded a pair of home runs in 11 games?

“Your best pitch is better with a big league ball,” he says, “and your worst pitch is way worse, if that makes sense.”

That’s a concept even pitchers several years from the major leagues can grasp.

“I have some high school kids I play catch with in the off-season,” says Nationals reliever Dan Jennings, who takes a couple bags of big league balls home for the winter, “and they’re like, ‘Oh my gosh, it’s actually kind of doing what I want it to.’ And I grab a high school ball and it feels like I could cut my fingers on the laces.”

Jennings’ situation illustrates how integrating the ball at Class AAA isn’t a total fix. Many clubs keep their top prospects at Class AA, and in the Nationals’ case, they keep a handful of big league-ready veterans at their AA affiliate (Harrisburg, Pa.) to more easily summon them to the big leagues than their AAA club in Fresno (Calif.).

So why not use the major league ball throughout the minors?

Cost, certainly, is a factor. Major league balls are hand-stitched in Costa Rica, and the retail cost is around $15. When major leaguers hit a record number of home runs in 2017, prompting renewed insistences the ball was juiced, Major League Baseball commissioned a study gauging how balls produced in recent years performed.

While no firm conclusion was reached, the committee determined there were “changes in the aerodynamic properties of baseballs,” due in part to significant precision on the part of those producing the balls.

The home run rate ticked down last season, but it’s up again, and so are the objections from pitchers.

Or perhaps this is a permanent shift, at every level.

“I don’t like using the ball as the excuse,” says Orioles reliever Evan Phillips. “It’s just getting better players. Kids are advancing a lot faster than they used to. These younger players are hitting the ball harder.

“You hit the ball harder, there’s more chances for homers. That’s starting to leak more into the big leagues, and we’re starting to see a new wave of talent.”

Still, Phillips acknowledges that the Orioles’ Class AAA home in Norfolk (Va.) is far less a pitcher’s park than it was last season. And even hitters like Lowe are willing to admit the bounce off the bat is a little friendlier the higher you advance in the game.

“Balls you hit flush are going to be 450, 460 feet, instead of 410, but they’re gonna get out anyway,” he says. “But the balls that you mishit – and get an extra 25, 30 feet on ‘em – there’s your extra five, 10 home runs.”