I've always thought that big local derbies were over-rated.
Part of the appeal of football is that the sport is a source of both passion and rational analysis.
Local derbies tend to have an excess of the former and a deficiency of the latter.
There is too much running and not enough thinking. The matches rarely live up to expectations.
They also tend to bring social tensions to the surface - which in the hysterical conditions of contemporary South America is not a pretty sight.
Last week's first-leg match between these two great teams was nothing short of a disgrace
The big derby in my home city of Rio de Janeiro is Flamengo against Vasco da Gama.
Earlier this year I was on my way to one of their clashes in the giant Maracana stadium. As my bus approached the ground it was clear that the police were having problems maintaining order.
Thousands of supporters of both sides were threatening confrontation. In the chaos and confusion gunshots were fired.
Everyone on the bus threw themselves to the floor to
avoid the stray bullets. Children were crying and old people were worried out of their wits.
Further south in Argentina, the authorities tried to make sure that nothing similar would happen when the great Buenos Aires rivals Boca Juniors and River Plate were drawn to meet each other in the semi-finals of the Copa
Away supporters were banned from both legs. But preventing rival gangs of hooligans from meeting in and around the stadium is only part of the battle - especially if there are rival gangs of hooligans left on the pitch.
Last week's first-leg match between these two great teams was nothing short of a disgrace.
Referee Claudio Martin seemed out of his depth. But players are responsible for their own actions - especially when they have the experience of River's Marcelo Gallardo and Boca's Alfredo Cascini.
After a first-half flare up both were sent off. It was Martin's desperate attempt to impose order on a game that was already slipping out of control.
But it had the opposite effect. The pair initially refused to go, sparking off an eight-minute free-for-all involving players and members of the coaching staff.
Gallardo struck the low point. He tore his fingernails down the face of Boca keeper Abbondanzieri, leaving him with blood streaming down his face.
River finished the game with nine men. It would have been eight if Martin had been wise to centre-back Ameli's sneaky repertoire of kicks off the ball.
Boca were 1-0 winners. But it was not a game from which anyone can take any pride.
At least the two teams have a chance to restore their reputations in this week's second leg.
An entire continent will be watching, half expecting another battle to be decided by two falls or a submission.
Here's hoping that instead they provide a spectacle worthy of their respective traditions, and help restore
faith in South America's derby matches.