An 18-year-old Mastic man was hit by a car and seriously injured while changing a tire Friday morning on the shoulder of Sunrise Highway in East Patchogue, police said. The 7:14 a.m. crash occurred on the westbound side of Sunrise Highway, close to Route 112. Police said Jesse Mangan, 18, of Mastic, was replacing a flat tire on a vehicle when he was struck by a 2020 Hyundai Elantra driven by 35-year-old Tyrell Lansworth of Shirley. Mangan was taken to NYU Langone Hospital-Suffolk in Patchogue with serious injuries. Both the Hyundai and Mangan’s vehicle were impounded for safety checks.