Lattimore signed with the Seattle Seahawks as an undrafted free agent following the 2020 NFL draft on May 4, 2020.[1] He was waived during final roster cuts on September 5, 2020,[2] and signed to the team's practice squad the next day.[3] He was elevated to the active roster on January 9, 2021, for the team's wild card playoff game against the Los Angeles Rams, and reverted to the practice squad after the game.[4] He signed a reserve/futures contract with the Seahawks on January 11, 2021.[5] Lattimore was waived on August 23, 2021.[6]
Lattimore was placed on the injured reserve list by the team on May 3, 2023.[10] He re-signed with the Stars on September 30, 2023.[11] The Stars folded when the XFL and USFL merged to create the United Football League (UFL).[12]