PEORIA, Ariz. -- It’s still the Vedder Cup -- only now, it’s official.

For years, games between the Padres and Mariners have been informally known as “The Vedder Cup” -- a reference to Pearl Jam front man and Rock & Roll Hall of Famer Eddie Vedder, a one-time resident of both San Diego and Seattle.

As of 2025, the Vedder Cup is a formalized competition. The two clubs announced the creation of a season rivalry series, with the winner taking home a trophy, featuring a guitar provided by Vedder himself.

As part of the competition, the Padres and Mariners will also partner to support EB Research Partnership, a charity co-founded by Eddie and Jill Vedder as a trailblazing nonprofit organization dedicated to funding research to discover treatments and cures for Epidermolysis Bullosa (EB).

“We are thrilled that we were able to bring the Vedder Cup concept to life in such a fun and impactful way,” Mariners executive vice president and chief operating officer Trevor Gooby said in a statement. “Creating and sharing memorable events like this with Mariners fans is extremely gratifying, and I am very thankful for Eddie, his team, EB Research Partnership and the Padres in sharing the Mariners’ vision and commitment to celebrating and serving the Seattle community.”

“We’re proud to partner with the Mariners and Eddie Vedder to announce the creation of the Vedder Cup, a special interleague rivalry series that celebrates the unique connection between our cities through the rock legend and Pearl Jam frontman,” Padres CEO Erik Greupner said in the statement. “This West Coast showdown will create some cool, fun, and memorable moments for our fans while bringing meaningful awareness to EB research. We can't wait to see this rivalry series grow and look forward to battling the Mariners for the Vedder Cup."

The Padres and Mariners have a long history of facing each other during Interleague play as natural rivals. It’s how the “Vedder Cup” moniker came to be in the first place.

In the first formal edition of the Vedder Cup, the Padres will host the Mariners May 16-18, before games in Seattle Aug. 25-27. Both clubs will host Vedder Cup theme games, and merchandise for the event will be available at both team stores.

With six games on the schedule between the two clubs, Friday’s announcement also included a potential tiebreaker. The first part of that tiebreaker is somewhat standard. The second part is unique:

1. Run Differential – The team with a greater run differential in the season series.
2. EV (short for Exit Velocity and Eddie Vedder) – If the clubs share an even run differential in the season series, the team with the highest exit velocity recorded on a hit will win the Vedder Cup.

The Mariners and Padres have played almost annually since 1997 (with only the 2017 season not featuring Interleague games between the two). In the history of the informal version of the Vedder Cup, Seattle leads the all-time series 68-63.