Which Vinkings player picked up a fumble and ran 66 yards to the wrong end zone for safety?

During the game at San Francisco in 1964 Defensive end Jim Marshall did that. He made it all the way to the end zone without realizing his mistake. Marshall and the Vikings still won the game 27-22. At the time of his retirement, Jim Marshall owned the career records for most consecutive starts (270) and games played (282).