All four players declined the assignment and elected for free agency.
Martinez signed with the Mets last offseason and looked to be fighting for a sport as a right-handed power bat off the bench, but a torn meniscus in spring training ended his season before it ever really began.
The 27-year-old Peraza provided some nice depth for the Mets in the middle infield when they needed it most, as players like Francisco Lindor, Jeff McNeil, and Luis Guillorme – among others – landed on the IL and missed playing time. He appeared in 64 games with a .204 average.
Oswalt has appeared in 26 game for the Mets over the past four seasons, making 14 starts to provide some depth in the rotation. Overall, he pitched to a 5.89 ERA in 94.2 innings.
Stock was claimed off waivers from the Chicago Cubs this past June. As the Mets dealt with more than their fair share of injuries in the starting rotation, Stock made two spot starts for the Mets, pitching to 5.40 ERA in 5.0 combined innings
Source: Yahoo Sports