Argentina crashed to a 1-0 defeat against Paraguay in South America's 2018 World Cup qualifiers as two goals from Arturo Vidal helped Chile reignite their campaign with a victory over rivals Peru.
A superb counter-attacking goal from striker Derlis Gonzalez on 18 minutes was enough to give Paraguay all three points in their match with Argentina as the hosts once again struggled to plug the gap left by injured talisman Lionel Messi.
Argentina rallied furiously in the second half, with Angel Di Maria seeing a goal from a free-kick disallowed because of a foul while both Gonzalo Higuain and Sergio Aguero went close.
But with Paraguay goalkeeper Justo Villar in defiant form between the posts, the visitor held on for a battling victory which revives their hopes of snagging one of the qualification berths.
The win left Paraguay just one point behind Argentina in the standings after 10 games. Argentina occupy the fifth qualifying spot in the table with 16 points, with Paraguay just behind on 15 points.
Chile meanwhile remain outside the qualification places despite their 2-1 victory over Peru in Santiago in the regional derby known as the "Clasico del Pacifico."
Chile, the dominant force in South American football over the past two years with back-to-back wins in the Copa America, desperately needed three points to get back on track after a stuttering start to the qualification campaign.
Bayern Munich midfielder Vidal got "La Roja" off to a dream start, heading home on 10 minutes to put Chile 1-0 up.
But a bold second half display from Peru was rewarded on 76 minutes when Edison Flores skipped clear on the edge of the area to rifle home a low shot to make it 1-1.
It seemed as if Peru had done enough for a share of the points but with time running out, Vidal found space near the edge of the penalty area and lashed home a low shot to beat Pedro Gallese.
Chile's win leaves them seventh in the standings with 14 points, two points from the qualification places.
Earlier, leaders Uruguay were held to a 2-2 draw by fourth placed Colombia in an entertaining duel in rain-swept Barranquilla.
Center-back Yerry Mina headed Colombia's equalizer five minutes from time after goals from Cristian Rodriguez and Barcelona superstar Luis Suarez had helped Uruguay into a 2-1 lead at the Estadio Metropolitano.
Colombia had taken the lead through Abel Aguilar after 15 minutes to open the scoring.