On May 8, 1973 — For the second time in his career, Pirate Willie Stargell poles one out of Dodger Stadium. His blast off Andy Messersmith hits the right field pavilion roof 470 feet away. His first home run, a 506-foot shot, came off Alan Foster on August 5, 1969. No other player has hit a fair ball out of the stadium. Los Angeles wins, 7 – 4.

Source:
Baseball Reference May 8