We had a shout early on for a penalty/free kick early on. From my position I couldn't tell if it was inside or outside the box. The referee waived play on.
My impression was that from the way he controlled the game he wanted to keep play flowing, or as flowing as it could be in that hellish heat. More significantly, he wanted to avoid any controversial decisions that prompted bad feeling and niggling among the players.
Another commentator has pointed out that there was only one brief outbreak of handbags. Given the heat and the effect it might have had on tempers things might have got a lot worse.