River Plate twice came from behind to earn a 2-2 draw with Argentina rivals Boca Juniors in Sunday's first leg of the Copa Libertadores final.
The tie had initially been due to take place on Saturday but was postponed because of heavy rain.
Ramon Abila put Boca ahead in the first half before Lucas Pratto equalised.
Dario Benedetto restored Boca's lead just before the interval but Carlos Izquierdoz put through his own goal to ensure the game ended all square.
The second leg of the final will take place at River's Monumental stadium on 24 November.
Sunday's encounter marked the first time in the 58-year history of the Copa Libertadores that River and Boca - who have one of the fiercest club rivals in world football - had met in the final.
Away fans were banned from attending the game because of safety concerns but Boca fans had La Bombonera stadium rocking all on their own.
However, despite the absence of their fans, River settled better than their opponents and they are level going into the second leg, which will be played in front of their own fans.
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