World Cup Group B kicked off on Friday with Carlos Queiroz's Iran taking on Morrocco.
With Spain and Portugal battling it out in the other fixture, this was a must-win game for the two teams if either was going to have anything more than an outside chance of scraping into the Round of 16.
Despite flashes of attacking intent from both sides, the game seemed to be heading towards a stalemate until late drama sealed the three points for Iran.
After Iran won a free kick late in the game, they profited from Aziz Bouhaddouz's decision to get his head on the ball which saw him put the ball into his own net. The result was harsh on the African side who had good chances in both halves of the game.
Bouhaddouz's own goal gave Iran their first win at a World Cup since 1998 and they now sit atop the group with Spain drawing 3-3 with Portugal later in the day.
Here are five things we learned from the game: