Following their trade for Javier Báez and Trevor Williams from the Cubs and before their game against the Reds tonight at Citi Field, the Mets made some roster moves, designating pitchers Akeem Bostick and Nick Tropeano for assignment to make room for the new acquisitions on their 40-man roster. In addition, the Mets transferred Sean Reid-Foley to the 60-day injured list as they activated Carlos Carrasco—who had been on the 60-day injured list himself.
With that, the Mets have mostly set their 40-man roster for the rest of the season. If other players on the 60-day injured list return, they will need to make room on that roster, but there are no waiver trades in baseball by which the Mets could add new players from outside the organization in August. It’s possible that the Mets could simply claim a player off waivers from another team, but it’s likely that the players who will make the push for the National League East title and possibly a run into the playoffs are now within the organization.