Colombia edged to the brink of their first World Cup since 1998 on Friday, securing a 1-0 win over Ecuador in a rain-delayed game disrupted by a half-time floodlight failure.
A first-half goal by AS Monaco striker James Rodriguez secured all three points for the Colombians, who are now guaranteed at least a play-off spot from South America's nine-team qualifying competition.
The victory put Jose Pekerman's team level with Argentina on 26 points at the top of the standings and both teams can seal qualification in Tuesday's next round.
Ecuador however, who were reduced to 10 men early in the game when Gabriel Achilier was dismissed, could have snatched an unlikely draw if captain Walter Ayovi had not missed a second-half penalty.
A pre-match deluge at Barranquilla's Estadio Metropolitano had appeared to leave the game in jeopardy at one point, with parts of the field covered in large pools of water as the rain tumbled down.
However the stadium ground staff worked ferociously to clear the excess water and after a 90-minute delay, Brazilian referee Heber Lopes got proceedings under way.
A lacklustre opening period saw neither side manage to gain control of the contest, and it was Ecuador who went closest to scoring when Jefferson Montero's swerving shot effort was punched away by Colombia goalkeeper David Ospina in the 18th minute.
But the complexion of the game changed decisively on the half-hour mark when Ecuador were reduced to 10 men, Achilier sent off for bringing down Colombia's Teofilo Gutierrez as he sprinted clear on goal.
The dismissal energised the Colombians and within a minute they had taken the lead through Monaco youngster Rodriguez.
Monaco team-mate Radamel Falcao -- named in the starting line-up after recovering from an ankle injury -- unleashed a ferocious long-range effort which Ecuador's stand-in keeper Maximo Banguera could only parry away.
The rebound fell kindly to Rodriguez who rifled home an angled low shot to put Colombia 1-0 up heading into the half-time break.
A floodlight blackout then delayed the start of the second half for 15 minutes, and there was a further interruption soon after the restart when Colombia keeper Ospina received medical attention for several minutes after a heavy blow to the head.
Ecuador were then presented with a golden chance to get back on level terms when Colombia defender Carlos Sanchez hauled down Manchester United winger Antonio Valencia in the box on 61 minutes.
But Ayovi miscued his spotkick horribly and Colombia escaped to claim a win which puts them within touching distance of a first World Cup since their appearance at the France finals 15 years ago.
With Chile defeating Venezuela 3-0 in Santiago to move up to third, Ecuador dropped down to fourth.
Chile's hopes of claiming one of the four automatic qualifying spots were given a huge lift thanks to goals from Eduardo Vargas, Marcos Gonzalez and Arturo Vidal.
Chile now have 24 points, two behind Argentina and Colombia although they have played one game more.
Ecuador remain in control of their destiny however, and are a comfortable five points clear of fifth-placed Uruguay, who met Peru in Lima later Friday.
Uruguay, semi-finalists in 2010, desperately need a victory to boost their chances of securing at least a play-off spot against the winner of the Asia zone play-off between Jordan and Uzbekistan.
Elsewhere Friday, Paraguay moved off the bottom of the standings with a 4-0 thrashing of Bolivia in Asuncion.
Goals from Jonathan Fabbro, Roque Santa Cruz, Richard Ortiz and Gustavo Gomez secured the win for Paraguay but the victory is likely to have come too late to save the 2010 World Cup quarter-finalists from elimination.