Mets fans visiting the team's website Wednesday afternoon were welcomed with a celebration, according to an ESPN report.
The site heralded the home team as "NATIONAL LEAGUE CHAMPIONS," and merchandise, including an orange and blue T-shirt that read "THE PENNANT WILL RISE," was on display.
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But the real life Mets had yet to play Game 4 against the Cubs.
Team spokesman Jay Horowitz told ESPN that the online display was a "glitch."
MLB executive Bob Bowman told ESPN that Major League Baseball Advanced Media controls the affected content on teams' websites. Bowman added that the league apologizes to the Mets for the error.
The Mets entered Wednesday's game with a 3-0 lead over the Cubs in the best-of-seven series. Leagues often prepare playoff merchandise for both teams beforehand and donate the losing team's gear to impoverished countries.
Steven Matz, the lefty from Stony Brook and Ward Melville High School, took the mound Wednesday opposite Jason Hammel, who was chased after allowing four runs in 11/3 innings.
For Mets fans, the celebration could be back on.