Tuesday night's incident in Milan, although shocking, was by no means a first, as regular followers of football will testify.
By Angus Loughran
Football commentator, Milan
But the appalling incidents achieved worldwide publicity for two extra reasons.
Juan Sebastian Veron watches as fireworks are thrown onto the pitch
Firstly a player - in Tuesday night's case AC Milan's Dida - was struck by a missile whilst on the field of play which to any sportsman should remain sacrosanct.
Secondly this was not a Serie A domestic clash, but the Uefa Champions League - Europe's premier club competition - being broadcast live around the world.
One of the most startling facts was the surprising lack of police who, incredibly, were in the stadium but chose to take positions on the forecourt outside instead of attempting to challenge those throwing the fireworks.
How could well over 100 fireworks be allowed in the stadium will be a question senior Italian football figures will be bringing up as a matter of urgency with the Milan club.
But when the same stadium is used for AC Milan's semi-final on 26 April, there will be fewer objects present.
Uefa - who have already punished Italian side Roma for a missile-throwing incident which hit Swedish referee Anders Frisk in the Champions League clash against Dynamo Kiev in Rome in September - are likely to punish Inter Milan seriously with a hefty fine and possibly a lengthy ban from European club competition.
They could also force them to play their matches either behind closed doors or at least 200 miles (300km) from Milan.
Italian sports violence
There has been much violence domestically in Italy this season.
But because of the increased media presence at Tuesday night's Champions League quarter final, the publicity and the action likely to be taken by the authorities will have a lasting effect on the game in general.
Football hooliganism which was rife in Britain in the 1970s and 1980s is largely under control thanks to a vast improvement in security measures taken by various police forces aided by undercover intelligence and decent stewarding.
Standing has been abolished in the premiership and there is no doubt the trouble is far more isolated in the UK, although the yob element still frequents the national game.
In Holland, the fans tend to riot when they win whereas British or Italian fans tend to object with anger when results turn against them.
And, although a far from valid excuse for what happened in the San Siro stadium on Tuesday, the trouble was sparked by an Inter Milan goal which looked perfectly legitimate to me being disallowed by the German official.
The lessons to be learned from Tuesday night are likely to be far reaching within the game but I doubt we have seen the last of this type of incident in the future.