In the marquee clash of the week, the 2002 champion Argentines pasted the two-time defending champion Chileans 3-0 to reach the final at the ATP World Team Championship.
French Open champion Gaston Gaudio got Argentina (3-0) going with a 6-4, 6-2 victory over Chilean slugger Fernando Gonzalez, who suffered his first-ever loss at this final French Open tuneup. "Gonzo" had been 15-0, including 10-0 in singles, on the red clay at Rochusclub.
Gonzalez captured singles bronze and doubles gold at last year's Athens Games.
The Argentines clinched their win over Chile (2-1) when Guillermo Canas got past dual-Olympic gold medalist Nicolas Massu 6-2, 1-6, 6-3 and they capped the matchup when their doubles tandem of Juan Ignacio Chela and French Open runner-up Guillermo Coria thumped a Chilean duo of Hermes Gamonal and Adrian Garcia 6-4, 6-3.
Chile, which defeated Australia 2-1 in last year's finale here, was trying to become the first-ever team to win this event three straight years.
The Red Group champion Argentina will meet Friday's Germany-Spain Blue Group winner on Saturday.
In other Day-5 round-robin action, France beat the Czech Republic 2-1 when a French doubles team of Arnaud Clement and Michael Llodra throttled a Czech pairing of Tomas Berdych and Jiri Novak 6-1, 6-1. The squads split the singles encounters when Sebastien Grosjean of France topped Novak 7-6 (7-5), 6-3 and Berdych blitzed Llodra 6-2, 6-1.
On Friday, the host Germans (2-0) will put Tommy Haas up against Tommy Robredo and Florian Mayer in against David Ferrer, with the doubles match yet to be determined. Spain (2-0), like Germany and Argentina, has yet to lose this week.
This eight-nation event also features the 0-2 United States and 0-2 Sweden, who will square off on Friday to wrap up their weeks.