Baseballs are suddenly flying far at a time when a manufacturing error has left many of them with a yellow discoloration, but Major League Baseball doesn’t believe one has anything to do with the other.

Although MLB on Tuesday acknowledged that game balls are performing differently of late, the league so far does not see a connection between the pigment mishap and a ball that, for the last month, has been livelier than it has been since 2019, a season in which home run records were shattered.

The league said that “variation in performance” has led to a decrease in drag, which is a measure of how much a ball slows down in flight. Data shows the changes in drag, and the corresponding surge in batted ball distance, began around the start of June, and players say they have noticed that something is different.

“The baseballs are doing some weird things,” Detroit Tigers ace Tarik Skubal told The Athletic last week. “I don’t know if you guys are paying attention to that. They’re flying right now. Go look at the numbers and tell me that something’s not going on. There’s no coincidence.”

MLB’s game balls are produced by Rawlings, a company the league partially owns, and the maker has run into various quality-control issues in recent years with a product that is handmade.

“Rawlings and our scientists do not see any evidence to date that the yellow staining is related to this change in drag,” the league said in a statement Tuesday, in response to questions from The Athletic. “We will continue to monitor the performance of the baseball as the season progresses.”

The Major League Baseball Players Association declined comment.

Rawlings told MLB in early February that in about 50 percent of baseballs shipped for the 2026 regular season and spring training, “some excess oil from the yarn inside the baseball filtered through the leather cover of the ball, creating some yellow discoloration,” the league said in its statement.

Both Rawlings and an MLB laboratory — which operates out of the University of Massachusetts, Lowell — tested the balls, which were found to be “within specifications and performed consistent with prior years,” the statement continued. In February, clubs were looped in, as was the MLBPA. Additionally, balls that show “cosmetic imperfections” are removed, the league said.

“Rawlings has resolved the issue with the yarn supplier, but due to the necessary lead times associated with baseball production,” MLB added, “the balls without the staining will not be shipped to clubs until late in the 2026 season or early 2027.”

Two people who read a report of testing at the Massachusetts lab, and were not authorized to speak publicly about the study, said it did not include measures of drag.

Drag is now down in June, and similarly struck balls are traveling about eight feet further than they did earlier in the season.

“This is the craziest month for drag I’ve ever seen,” said one high-ranking research and development analyst for an MLB team, who spoke on condition of anonymity because they were not authorized to speak publicly.

While acknowledging that the drag decline is real, MLB did not offer a specific explanation for the phenomenon.

“MLB makes drag data available to the public on Baseball Savant and we are aware of the recent reduction in drag,” the league’s statement continued. “To be clear, there has been no change in the materials or manufacturing process of the baseball. Because the baseball is hand-sewn and is made with natural materials, we expect variation in performance both throughout the season and between seasons.”

Baseball Savant, a statistics website run by MLB, tracks the drag of the ball publicly and graphs a daily figure. The graph looks drastically different compared to any other year since the site started tracking drag in 2016.

MLB’s statistical analysts have created a metric to measure drag on the ball called drag coefficient. By looking directly at the velocity and spin out of the pitcher’s hand, and comparing that to the velocity of the ball when it reaches the plate, and then adjusting that number for weather effects, the metric reveals how much the ball is slowing down while spinning through the air. A lower drag coefficient means the ball will travel farther when put into play.

From June 1 through June 29, the drag coefficient was down .013 from last year’s full-season number, which suggests that batted balls that exit the bat at 100 mph or greater would fly around six to seven feet farther on average, by MLB’s own estimation. That meshes with what is actually happening.

How big of a deal is this? The ball in June has a lower drag coefficient than it has since 2019: the year of the home run. That season, batters hit 6,776 homers — 671 more than the next highest season.

After 2019, when batters homered in 3.6 percent of plate appearances, MLB made changes to the ball. By 2022 the homer percentage was back under 3 percent. This season, MLB saw a home run in 2.8 percent of plate appearances until June, when the rate suddenly spiked to 3.4 percent. While home runs generally rise as the weather warms, in recent seasons the June rate has hovered around 3 percent exactly.

The data shows balls flying surprisingly far by nearly every metric:

  • In June, home runs per batted ball hit a five-year monthly high.
  • Home runs as a percentage of barrels (a metric that groups the best-hit balls by exit velocity and launch angle), reached a five-year high for the month of June.
  • Barrels are traveling eight feet farther this month than they did in May.
  • The difference in barreled-ball distance between May and June of this year is the biggest May-to-June jump in the Statcast era (since 2015).

Looking at barrels hit only in domed ballparks — which helps to adjust for weather and contact quality — reveals a stark difference this past month in how balls have performed.

Much remains unknown about exactly how many balls were impacted by the manufacturing error, or how often they are in play. Every ball used in-game has mud applied to it, which can largely hide the discoloring on most balls. Umpires and catchers can throw out the worst-looking balls when they see them, and one MLB manager, granted anonymity to speak candidly, said more balls are being thrown out of play by the catchers than they ever remembered seeing before.

It is unclear whether there will be any resolution on these issues anytime soon — or why the ball is performing differently in June compared to prior months. And the continued uncertainty around the ball has left some players unsure what to believe.

“You can go down whatever conspiracy theory you want to go down,” said Skubal. “Manipulation of balls. Whatever. And you’ll probably get nowhere, because there’s no accountability on that side of adjusting baseballs, which is interesting, because there seems to be a lot of data out there, suggesting that — especially in 2019 — the balls were flying much farther than they used to. Now they’re doing it again. I don’t quite get it, but I guess I’m not meant to understand.”

— Cody Stavenhagen contributed to this report.