The second leg of the Copa Libertadores final between River Plate and Boca Juniors had to be postponed for 24 hours on Saturday as a result of an attack on the Boca team bus. River fans clashed with police outside the stadium as tear gas and rubber bullets were fired. But the violence is only part of the story.

There were desperate attempts to stage the game on its scheduled day, first with an hour’s delay, at 6pm local time, and then at 7.15, 7.30 and 7.45, before the abandonment was finally announced to deafening whistles from the 70,000 inside the ground at around 7.20. A large part of the fallout will concern who applied pressure to whom and what machinations occurred in the three and a quarter hours after the attack.

Copa Libertadores final put back 24 hours after River fans attack Boca bus - as it happened Read more

The mood had seemed excited and expectant as River fans descended on the Stadio Monumental, while Boca fans, thanks to the ban on away fans in Argentina, made for their home ground, La Bombonera, eight miles away, to watch on a giant screen.

But when the police escort, surprisingly according to locals, led the Boca bus on to Avenida Monroe a little after 4pm, it was surrounded by River fans who pelted it with missiles. Video subsequently released by the club showed at least five smashed windows.

A video taken on a phone inside the bus shows Boca players chanting only to fall abruptly silent as the first missile strikes. As an official holds a curtain over the broken glass, the Boca midfielder Pablo Pérez turns away and slumps, clutching his face.

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Tear gas then entered the bus, although it is not clear whether that was from police seeking to disperse the crowds or from River fans targeting Boca players, as their players were targeted at La Bombonera in the Libertadores three years ago. On that occasion, River were awarded the game. Forensics experts were seen swabbing the bus, presumably to determine the origin of the gas.

“There are many players who were coughing, with the feeling of needing to vomit,” said Carlos Tevez. “As for me, I had a lot of pain in my throat and just now it was giving me a headache.”

The bus driver revealed he fainted and the bus would have crashed had a Boca vice-president, Horacio Paolini, not grabbed the wheel.

Trouble continued with thousands of River fans breaking through security, so many without tickets were able to force their way into the stadium.

Pérez was taken to hospital with an eye injury but the medical team of Conmebol, the South American federation, released a statement saying neither he nor any Boca player was unfit to play. Pérez was then named in the starting lineup. Boca, though, clearly did not wish to play. Tevez said they were being “obliged” to do so despite “being in no condition” while the midfielder Fernando Gago blamed the presidents of Conmebol and Fifa.

It may also be that the president of Argentina, Mauricio Macri, a former president of Boca, had reasons to get the game played: he will host the G20 summit in Buenos Aires, starting on Thursday.

The Boca president, Daniel Angelici, said: “We’ve had stones thrown at us before ... I always say matches are won and lost on the pitch, but we were not in the right condition to play today.” He thanked River for supporting Boca in their desire to postpone the game.

As time drifted by and delay added to delay, it came to seem increasingly that the match, billed as the derby to end all derbies, would never start. When the announcement finally came, after the initial jeers and whistles, those in the stadium filed away relatively calmly, although there were some scuffles. The damage, though, to the spectacle and to the reputation of Argentinian football had already been done.