Argentina, weakened by the last-minute suspension of Lionel Messi, suffered a fourth defeat in their World Cup qualifying campaign as a spirited Bolivia won 2-0 in La Paz on Tuesday.
Bolivia scored either side of halftime through Juan Arce and Marcelo Martins and were deserved winners against an Argentina side who defended poorly throughout an exciting end-to-end encounter.
The defeat left twice World Cup winners Argentina provisionally third on 22 points in the 10-team South American qualifying group, but with Chile, Ecuador and Colombia all within two points and with a game in hand.
Argentina were already without suspended regulars Javier Mascherano, Lucas Biglia and Gonzalo Higuain and their task was made even tougher when captain Messi was handed a four-match ban for swearing at a match official hours before the game started.
Bolivia appeared fired up by the decision and got the goal their early pressing deserved through Arce after 31 minutes.
The skinny winger outmuscled Facundo Roncaglia on the penalty spot to head home a deep cross from Pablo Escobar on the right.
Roncaglia was at fault again for the second goal seven minutes into the second half.
The Celta Vigo defender failed to prevent Jorge Flores from escaping to the byline to cross for an unmarked Marcelo Martins.
The big striker had all the time in the world to steady himself and hammer the ball past helpless Argentina goalkeeper Sergio Romero.
Argentina came into the game more when Sergio Aguero replaced Angel Correa 10 minutes into the second half but they could not get a goal and they are now likely to slip down the South American qualifying table.
The top four teams qualify automatically for Russia 2018 and the fifth-placed side goes into a playoff with a team from Oceania.
Fourth-placed Colombia and Ecuador, in fifth, play later on Tuesday, while Chile, in sixth, face bottom side Venezuela.