However, it was later confirmed the game had been suspended until 5pm local time (8pm United Kingdom time) on Sunday.
Things got wild when a Boca team-bus tried to wind its way through the streets of Buenos Aires en route to the stadium amid a sea of River Plate fans, who hurled projectiles at the vehicle as it sped past.
The trouble began as Boca's team bus approached the stadium.
"I want to say to our families that we are fine because have not had any contact in the changing room".
And another video showed the ambush by fans.
"Because of the wind and the broken windows, it entered the bus". Forensics experts were seen swabbing the inside of the bus, presumably to ascertain the origin of the gas.
Boca's captain was left with glass in his eye after the bus attack.More news: Trump eager to ‘turn a blind eye' to Khashoggi murder - Turkish FM
A group of River fans pelted the bus with stones and gas as it arrived at the Monumental stadium in the upmarket Nunez neighborhood of Buenos Aires. On that occasion, Boca were disqualified from the competition.
According to TyC Sports, Perez was sent to a hospital via an ambulance after suffering cuts to his arm, while one of his eyes had splinters in it from the shattered window glass. Pérez was then named in the starting lineup. They're forcing us to play. "But the truth is we're not in condition to play".
Second, physical injury was suffered by at least two Boca players as a effect of splinters of glass from the broken windows.
The South American Football Confederation (CONMEBOL) said it had initially delayed the match "due to the incidents with the Boca Juniors team bus". CONMEBOL president Alejandro Dominguez also mentioned illustrious guests, such as Federation Internationale de Football Association president Gianni Infantino.
He had also promised that the move to a one-off final from next year would be safe, but after this chaos, the thought of what might unfold were tens of thousands of Argentinians supporting rival clubs to make the journey west to Santiago, where next year's showpiece will be held, is deeply disturbing.
All of which leads to an obvious question: Why did it take so long to decide that the game should be pushed back to Sunday?
In anticipation of yet more ugly scenes, it had been suggested that the rearranged match would take place behind closed doors, but later confirmed that the match would in fact be played in front of fans. The damage, though, to the spectacle and to the reputation of Argentinian football had already been done.