Rams rookie safety John Johnson III made his first start, grabbed his first interception and nearly scored his first touchdown in a 16-10 loss to the Seattle Seahawks on Sunday. If only he hadn’t run out of gas 19 yards short of the goal line at the Coliseum. Johnson stepped in front of tight end Luke Willson to intercept a pass by Russell Wilson in the second quarter and returned it 69 yards, pausing once for a blocker and then running out of steam, he admitted after the game. “That’s something I have to work on,” Johnson said. “I’ve got to get to the end zone.” The Rams converted the interception into a field goal to take a 10-0 lead in the second quarter. Johnson, a third-round pick from Boston College, also deflected two passes and made three tackles.