How the Keith Hernandez trade helped take Mets from rebuilding to contentionThe Mets acquired Hernandez from the Cardinals on today's date in 19836/15/2020, 3:10 PMFLUSHING, NY: Keith Hernandez #17 of the New York Mets watches the flight of the ball as he heads to first base during a game at Shea Stadium in Flushing, New York. Hernandez played for the Mets from 1983-1989. (Photo by MLB Photos via Getty Images) / MLB Photos/Getty Images