Complex sentence: Then, the opposing team scored two more runs before the final score was 5--4, the batter on the winning team who batted in the third run would be credited with the game-winning RBI, even though the losing team scored four runs.
Split into simpler sentences: Then, the opposing team scored two more runs, making the final score was 5--4. The batter on the winning team who batted in the third run would be credited with the game-winning RBI, even though the losing team scored four runs.