This is a regular-season Major League Baseball game between the Philadelphia Phillies and the Seattle Mariners held at T-Mobile Park in Seattle. The Mariners serve as the home team in their retractable-roof ballpark while the Phillies visit as the National League opponent, making it an interleague matchup on the MLB 2026 schedule. The game is part of each club’s pursuit of postseason positioning and showcases two established major-league franchises in a professional baseball setting.