The Metropolitan Police and the Football Association will be making sure today that the scenes in Manchester between Rangers and Russian fans are not repeated, with an unprecedented show of force.
More than 1,000 police officers will be on the streets to ensure the showpiece event of the football season - the FA Cup - passes off peacefully.
There will be a "zero-tolerance" approach to crime at the FA Cup final, and fans will be arrested if they are seen to breaking the law.
Tens of thousands of fans are expected to flock to London from the south coast and South Wales as minnows Cardiff City take on firm favourites Portsmouth.
Both clubs have sold their 25,000 ticket allocation and thousands more fans are expected to make the trip to soak up the atmosphere of Cup Final day.
Bookies are giving Portsmouth the edge to win the tie.
