3. Trading Brandon Nimmo to Pittsburgh for Andrew McCutchen
The Mets were coming off an abysmal 2017, having finished with a 70-92 record after having World Series aspirations on opening day. At the trade deadline, Sandy Alderson traded away much of the roster including outfielders Jay Bruce and Curtis Granderson, meaning the Mets had holes to fill. The Pittsburgh Pirates were beginning a rebuild after trading Gerritt Cole to the Houston Astros. McCutchen was the definition of an "Alderson-type player"- he walked, struck out a lot, and hit 20-plus home runs a season. It made sense at the time for Alderson to be interested in the former MVP.
The Mets had only one notable prospect at the time in Gimenez. Rosario and Dominic Smith were viewed as the 2018 shortstop and first baseman by the organization, meaning the Mets had only one other young and upcoming player- Brandon Nimmo. Though he was solid when on the field in 2017, Nimmo could never shrug off the "injury-prone 4th outfielder" label. He had just played 69 games in 2017 and was highly underrated even though he hit .271 with 5 home runs.
This trade could have been amongst the worst trades in franchise history along with Tom Seaver and David Cone back in the 1970's and 1990's. McCutchen never regained his MVP form with the San Francisco Giants in 2018 and hardly played during his tenure with the Phillies. Nimmo has become a franchise Met, someone all the fans gravitate to. With all the criticism Alderson received in 2017 when he said, "We never considered Stanton because we have Nimmo", he ended up being correct about that decision.