 The reason this occurred is because the workers at the stadium left the lights switched on the day before the match which attracted huge swaths of insects.The players and coaches of each team during the warm-up tried swatting the moths, and ground staff used brushes to clean moths from the walls, ground and other places.One moth was infamously captured flying on and around Cristiano Ronaldo's face when he was sitting on the pitch after being injured during the match.