At the end of July, New York Mets beat writer Mike Puma (New York Post) heard that the team would play a series against the Miami Marlins in Puerto Rico next year.
Repeating earlier Tweet: Hearing the Mets and Marlins will likely play a series next year in Puerto Rico. Announcement could be coming soon from MLB. Mets last played in Puerto Rico in 2010.
— Mike Puma (@NYPost_Mets) July 31, 2019
On Monday, those rumors and reports turned out to be true. Per the MLB Public Relations official Twitter account, the Mets will play a three-game series in San Juan, Puerto Rico next season against Miami.