Copa Sudamericana: Boca Juniors 0 River Plate 0
Boca and River played out a 1-1 draw in the Argentine Primera Division last month that saw both teams finish the match with 10 men in sodden conditions at the Estadio Monumental Antonio Vespucio Liberti.
But neither side could make the breakthrough in a fiery clash at La Bombonera in Buenos Aires on Thursday.
A total of nine yellow cards were handed out by referee Silvio Trucco, with seven of those dished out to River players.
The stalemate was the first goalless draw between the bitter Argentine rivals since October 2005.
River will host the return leg on November 27 for a place in the decider of the second-tier South American competition.