On top of hitters such as Pete Alonso and Francisco Lindor, the Mets will be relying on some youth in Francisco Alvarez and Brett Baty to drive in runs. Designated hitter doesn’t have a locked-in bat, with names such as Ji-Man Choi and Luke Voit candidates for the role. Signing JD Martinez gives the Mets another powerful slugger in their lineup, providing more consistent production and insurance if the young hitters don’t pan out.