A truck struck a 40-year-old Bronx pedestrian before fleeing Friday night — leaving the helpless victim in the street, where he was fatally finished off by a passing SUV, police said Sunday. A crutch and bloodstains could be seen in the middle of the roadway at East 138th Street and Bruckner Boulevard after the 7:30 p.m. horror. An SUV fatally hit a Bronx pedestrian after the victim was sent to the pavement by a truck, police said. Peter Gerber The victim had been crossing the road outside its marked crosswalk when the truck slammed into him, sending him to the pavement, cops said. A 61-year-old driver in a 2015 Hondo CR-V was heading in the same direction as the truck and had no time to stop before striking the man on the ground. A crutch, purple gloves and blood remain the roadway after the horror. Peter Gerber Paramedics rushed to the scene after a 911 call was placed and raced the victim to Lincoln Hospital, where he was pronounced dead.…