ORCHARD PARK, NY - AUGUST 08: Christian Wade #45 of the Buffalo Bills runs in the back field during the fourth quarter of a preseason game against the Indianapolis Colts at New Era Field on August 8, 2019 in Orchard Park, New York. Buffalo defeats Indianapolis 24 -16. (Photo by Brett Carlsen/Getty Images)
Shortly after the season, the NFL teams sign players who usually manned their practice squad to future/reserve contracts which puts them on the roster before the start of the new league year. The contracts are used to keep players from signing with other teams during the offseason.