Bryce Harper's Under Armour Cleats Celebrate Baseball Rivalries

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One of the most decorated MLB players, Philadelphia Phillies first baseman Bryce Harper, has introduced the Under Armour Harper 10 in a big way. Known for challenging the status quo on his feet, but also with his gear, Harper has a Hall of Fame resume in cleats.
With Under Armour leading the way, Harper has rocked stylish cleats for a decade. Under Armour was aggressively building its baseball footprint with Harper at the forefront, when he was seen as the face of the next generation of the sport.
Harper became one of the few MLB players to receive a signature cleat line, beginning with the Harper One in 2016. The series has continued annually, reaching the Harper 10s in 2025, making him one of the longest-running baseball players with a signature shoe line.
Among his standouts early on were the cleats honoring Betsy Ross. He went rogue without Under Armour in 2020, wearing his Kobe 6-inspired cleats for Kobe Bryant. Even earlier this year, he brought the Juice to Spring Training.
The collaboration portion of his cleat game is unmatched. Last season, he built the case study for rolling out a capsule collection for fans. Between Philadelphia's local landmark, Wawa, and the baseball card-inspired style was evident in the Harper 9s.
Bryce Harper discussing his Mets-colored cleats pic.twitter.com/Ygb4bH8uK2
— John Foley (@2008Philz) August 26, 2025
Harper's admiration for the Phillies' mascot, Phillie Phanatic, has inspired him to show his largest green pal that he can rep him on the field.
Harper has been known to integrate brands like Supreme, honor players like Jose Fernandez or Jackie Robinson, hop in a Miami Vice mode, and represent the Nation's Capital in the Home Run Derby.
The creativity behind Harper and Under Armour started back in 2011 when he signed as an 18-year-old. The brand, stationed in Baltimore, Maryland, was in the backyard of Harper's while he debuted with the Washington Nationals. Fifteen years later, and they are breaking the mold with Harper's Rivalry Pack.
The Rivalry Series features 'The Three Line,' 'Chop ATL,' 'Miami Bryce,' and 'Capital Star'. Aptly designed for his division rivals respectfully, the New York Mets, Atlanta Braves, Miami Marlins, and his former team, the Washington Nationals.
On Monday night, he lit the rivalry on fire and ignited Mets fans with his color way. This could be part of the last month of baseball as the Phillies take on the Braves this weekend and Miami the following weekend.
Athletes and fans can shop Harper's signature collection at UA.com. In the meantime, they can expect more heat from the MLB All-Star ramp-up for the postseason.
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Dr. Caleb Mezzy is a college professor in New Jersey leveraging his decade of sports marketing and branding experience. He has worked with various brands, teams, athletes, and sports organizations on their marketing efforts. An avid collector of cards and memorabilia, he can be found on Instagram at @caleb_mezzy or via email: CSMezzy@gmail.com.