Uruguay overcame the thin air at high altitude for their first win in 10 qualifiers in La Paz while Colombia beat Peru in temperatures of 35 degrees Celsius and high humidity in Barranquilla on the Caribbean coast.
Defenders Martin Caceres and Diego Godin scored for Uruguay in the absence of suspended strikers Luis Suarez and Edinson Cavani while the frustrated Bolivians had Jair Torrico sent off after 71 minutes.
"It's the first time we've won here, the team had order and discipline... In the end, helped by the sending off, we were deserved winners," Uruguay coach Oscar Tabarez told reporters.
"It would have been suicidal to wait for Bolivia in defence and I think...in these atmospheric conditions, we did well," added Tabarez, who is serving a suspension for protesting refereeing decisions during Uruguay's Copa America quarter-final defeat by Chile in June and was forced to watch from the stands.
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Cavani was also serving a two-match Copa America suspension while Suarez is still seeing out his nine-match FIFA ban for biting Italy's Giorgio Chiellini at last year's World Cup finals in Brazil.
NEW COACH
Bolivia were playing their first competitive match under new coach Julio Cesar Baldivieso, a member of the last Bolivian team to play at the World Cup finals in the United States in 1994.
"We had 10 days work to face a monster like Uruguay... If I'm not mistaken maestro Tabarez has been in charge of their national team for (nine) years," he said.
In Barranquilla, Teofilo Gutierrez scored from a 36th minute header following a corner for 2014 World Cup quarter-finalists Colombia, who were without injured playmaker James Rodriguez.
Peru striker Paolo Guerrero hit the post early in the second half and Colombia goalkeeper David Ospina saved Christian Cueva's free kick brilliantly before substitute Edwin Cardona scored the second goal in added time.
"We had chances to draw the match, my team finished in good physical and footballing shape, I liked how we played though not the result," said coach Ricardo Gareca, who is looking to qualify Peru for their first finals since 1982.
Argentina, without the injured Lionel Messi, were at home to Ecuador and Brazil, missing the suspended Neymar, were away to Chile in later matches.
(Reporting by Malena Castaldi in Montevideo and Luis Jaime Acosta in Bogota; Editing by Greg Stutchbury)
