What are these bare-chested guys doing at Astros games? The viral ‘Tarps Off’ movement, explained

HOUSTON – For generations, baseball fans have brought gloves, scorecards and rally towels to the ballpark.

Now, some are bringing something else: absolutely no shirts.

A growing fan phenomenon known as “Tarps Off” is sweeping through Major League Baseball, transforming sections of stadiums into seas of shirtless fans twirling T-shirts overhead like helicopter blades.

What began as a small gathering in the right-field stands at Busch Stadium in St. Louis has quickly become one of baseball’s most unexpected traditions of the 2026 season.

The trend has spread to ballparks across the country, including Houston, where fans joined the movement during the Astros’ recent series against the Pittsburgh Pirates.

At first glance, the scene looks more like a college football student section than a Major League Baseball game.

One fan removes his shirt.

A few others follow.

Soon dozens are standing shoulder-to-shoulder, bare-chested and spinning shirts over their heads with every big moment.

In St. Louis, the movement has become something of a good-luck charm.

The Cardinals entered the season expected by many to be rebuilding. Instead, they opened with a surprising 29-18 record fueled by breakout performances from Jordan Walker and JJ Wetherholt.

Then came Tarps Off.

According to MLB.com, the trend first appeared during a Cardinals game against the Kansas City Royals. A small group of fans in the right-field stands removed their shirts and began waving them around. As the game continued, more spectators joined until much of the section was participating.

The Cardinals won that game on a walk-off hit.

The origins of the movement trace back to members of the Stephen F. Austin club baseball team, who attended the game and helped launch the trend.

The following day, Cardinals manager Oli Marmol embraced the phenomenon, purchasing tickets in the section and inviting the students into the clubhouse.

Days later, Tarps Off gained even more momentum.

With the Cardinals facing the Pittsburgh Pirates in extra innings, catcher Iván Herrera crushed a walk-off three-run home run in the 10th inning. As he rounded the bases, Herrera acknowledged the shirtless section. After crossing home plate, he removed his jersey and twirled it in celebration.

By then, Tarps Off had become more than a quirky fan moment.

It had become baseball’s newest movement.

The trend has since appeared at games involving the Tampa Bay Rays, Seattle Mariners, Detroit Tigers and Philadelphia Phillies.

Social media videos have helped fuel its growth, introducing the concept to fans hundreds of miles from St. Louis.

While the current baseball craze feels new, the roots of shirtless sports fandom run much deeper.

According to reporting by The Athletic cited by MLB.com, a modern version of the movement gained traction during the 2025 college football season at Oklahoma State. A fan reportedly accepted a $10 bet from his sister to stand shirtless in an otherwise empty section and wave his shirt overhead during a difficult season for the Cowboys.

Other fans soon joined him.

The tradition spread throughout college football, appearing at games involving teams ranging from struggling programs to eventual national champion Indiana.

The movement even surfaced during an outdoor hockey game at Penn State’s Beaver Stadium in January temperatures that would make most fans reach for an extra jacket, not remove one.

Baseball, however, may have provided the perfect stage.

The sport’s long season, relaxed atmosphere and communal nature make it easy for fans to join in. Unlike organized chants or coordinated traditions that require participation from an entire stadium, Tarps Off needs only a few willing volunteers to get started.

The Cardinals are already treating the trend as more than a passing fad.

The club announced the upper right-field bleachers at Busch Stadium will become a dedicated high-energy fan section open to fans regardless of where their original seats are located.

And yes, shirts remain optional.

Whether Tarps Off becomes baseball’s next enduring tradition or fades as quickly as it appeared remains to be seen.

For now, though, one thing is clear. Some of baseball’s loudest fans aren’t waving rally towels anymore. They’re wearing them.