With the match tied at 0-0, Rooney and Ricardo Carvalho were challenging for the ball when the Englishman appeared to stamp on the defender.
To this day, there are those who would say it was unavoidable and others who deem it nothing short of assualt. Such is football.
Cristiano Ronaldo was clearly in that second camp. He immediately ran over to the referee and appealed for maximum punishment, getting a shove from Rooney as thanks.
The referee was convinced and brandished a red card, sending off England's star player. Normally, this wouldn't be enough to draw such criticism, but it was everything that followed that fanned the flames.
Cameras caught Ronaldo winking as Rooney trudged off the pitch, giving the English press all they needed. Here was a young player, who while undoubtedly talented, pressuring a referee to get someone sent off. A team mate at club level no less.
Earlier in the game, Ronaldo had led into Rooney with a headbutt that suggested maybe they weren't as close on the training ground at Carrington as people thought.
It was the beginning of Ronaldo's reputation for petulance and cheating that has still never fully left him in England. Rooney and Ronaldo made their peace before the beginning of the following Premier League season, as the pair went to lead Manchester United to one of the most successful periods in their history.
Portugal went on to win the game on penalties after England had a goal disallowed in extra time.