Chicago Cubs vs Seattle Mariners is a Major League Baseball regular-season game held at T-Mobile Park in Seattle. The matchup features the National League’s Cubs visiting the home ballpark of the American League’s Mariners, a retractable-roof stadium that serves as the Mariners’ primary venue. The game is one of the scheduled contests in the MLB 2026 season and showcases nine-inning professional baseball between two long-standing major league clubs.