Argentinean giants Boca Juniors and Newell's Old Boys played out a goalless draw in the first leg of their Copa Libertadores quarter-final.
Boca enjoyed better of the opening exchanges, but could not find a way through as Nicolas Blandi failed to connect with a long ball inside six-yard box and an unmarked Guillermo Burdisso made a mess of his header from a corner.
Carlos Bianchi's side continued to enjoy the better possession during the second half and tried their luck with a number of long-range shots but could not beat Nahuel Guzman.
The best opportunity for Newell's to break the deadlock was when home keeper Agustin Orion produced a fine save to keep out Ignacio Scocco's shot from outside the box. Burdisso then picked up a second yellow card late on.
Guzman said: "They were superior during the first half, but during the second one we levelled it and the match was a midfield battle. There is still one match to go in our stadium and I believe we can book a ticket to the next round."
In the other quarter-final clash, Brazilian side Atletico Mineiro came from two goals behind to draw 2-2 against Tijuana in Mexico.
Near the half-hour mark, forward Diver Riascos fired Tijuana ahead and, at the beginning of the second half, Fidel Martinez netted the rebound when Victor saved Alfredo Moreno's shot from distance.
Atletico came back as Ronaldinho's corner was poorly cleared by Fernando Arce, with Diego Tardelli taking advantage, then in stoppage time Luan finished a one-on-one chance past Cirilo Saucedo to equalise.
Information from the Press Association was used in this report.