Argentina went three points clear at the top of the World Cup qualification standings in South America with a 2-1 win in Chile.
First-half goals from Lionel Messi and Gonzalo Higuain put Argentina 2-0 up at the break, before Felipe Gutierrez pulled one back for the hosts in injury time.
Real Madrid striker Higuain was taken off in the second half after apparently suffering an ankle injury following a tackle from Gonzalo Jara.
"We have forwards of huge standing who normally never forgive (mistakes). Argentina were sharper with their finishing," Argentina coach Alejandro Sabella said.
"We knew Chile would take the ball from us a lot and we had to be very concentrated in defence."
Argentina now have 20 points from nine games, three points ahead of Ecuador, who drew 1-1 in Venezuela after Segundo Castillo cancelled out Juan Fernando Arango's early opener for the hosts.
Colombia, who did not play on Tuesday night and subsequently have a game in hand, are in third place on 16 points.
South American champions Uruguay were crushed by Bolivia 4-1 to boost their hopes of qualifying with a hat-trick from striker Carlos Saucedo.
The Bolivians, always strong at home in high altitude, took the lead when Saucedo stole in to tap home from a corner. Gualberto Mojica then doubled the lead before the break as he slotted a fine free-kick past goalkeeper Fernando Muslera.
Saucedo then took over to make it 4-0 with two goals in five minutes in the second half before Luis Suarez scored a consolation free-kick after being brought down on the edge of the box.
Uruguay have takenonly one point from their last four qualifiers, while Bolivia have moved away from the bottom of the table. Last year's Copa America winners remain in fourth place, above Chile and Venezuela on goal difference.
Paraguay, beaten finalists in the Copa America last year, remain bottom despite beating Peru 1-0 in Asuncion thanks to Pablo Auilar's goal.