It was one of three scoreless draws, including a critical stalemate between Peru and Argentina in Buenos Aires which leaves those two teams locked in fifth and six place respectively, separated by goals scored.
A point behind them are Paraguay, who stayed alive courtesy of a late 2-1 win away to Colombia.
It leaves the Colombians and third-placed Chile, who beat Ecuador 2-1, a point clear of Peru and Argentina.
However, Colombia and Chile don't have easy assignments - away to Peru and Brazil respectively.
Paraguay, with the worst goal differential, face arguably the easiest final match, at home to last-placed Venezuela.
Two-time world champions Argentina have struggled badly but will fancy their chances away to Ecuador, who have lost their last five matches.
-AAP