The true significance of the Battle of Old Trafford on September 21, 2003 only became apparent months later.
In the immediate aftermath it was just the latest instalment of a series of no-holds-barred clashes between Manchester United and Arsenal at the top of the Premier League table.
But when Arsene Wenger's 'Invincibles' completed the 2003-04 season undefeated, minds were cast back to that tumultuous afternoon at Old Trafford as the closest Arsenal came to losing.
Had Ruud van Nistelrooy not clattered the crossbar with his last-minute penalty - leading to the Dutchman being jostled aggressively by several Gunners players, especially Martin Keown - Arsenal's amazing unbeaten season may not have happened.