JOIN USArgentina stay on course
Lionel Messi struggled in the thin air of La Paz, fluffing a gilt-edged chance to end his goal drought against Bolivia, while Colombia marksman Radamel Falcao was kept scoreless in Venezuela on Tuesday.
However, with a rampant Ecuador crushing Paraguay 4-1 in Quito, South America's top three teams remain in charge of their World Cup qualifying chances as the race for the region's fourth direct ticket to the 2014 finals in Brazil hotted up.
Uruguay, Copa America holders and the region's best-performing team at the 2010 World Cup, lost 0-2 in Chile and sank below the qualifying line as their opponents and Venezuela climbed above them into fourth and fifth.
Argentina managed well in the thin air at nearly 4,000 metres in La Paz to draw 1-1 with Bolivia, putting behind them the 1-6 defeat suffered by Diego Maradona's team four years ago.
But they might have won had Messi made the most of a late chance. Messi stole the ball from a defender and came face to face with Sergio Galarza but a moment's hesitation cost him dear and allowed the goalkeeper to block his shot.
That preserved Bolivia's record as the only South American team to have denied the little ace a goal.
Bolivia had much the better of the opening exchanges and went ahead in the 25th minute when striker Marcelo Martins rose above defender Hugo Campagnaro to head Alejandro Chumacero's right-wing cross past Sergio Romero.
Argentina, who had a good chance for striker Rodrigo Palacio saved by Galarza with his feet, equalised one minute before halftime. Messi beat two defenders and fed left back Clemente Rodriguez whose centre was headed home by midfielder Ever Banega past the diving Galarza.
Musical chairs for the top three places has Argentina at home to Colombia on June 7 and visiting Ecuador in Quito four days later after the Ecuadoreans' trip to Peru. Colombia host the Peruvians on their return from Argentina.
Uruguay have a bye on June 7 and will watch the middle positions in the table closely as Venezuela visit Bolivia and Chile travel to Paraguay.
Results: Bolivia: 1 drew with Argentina: 1; Ecuador: 4 bt Paraguay: 1; Venezuela: 1 bt Colombia: 0; Chile: 2 bt Uruguay: 0.