Washington - Mike Te'o scored three tries to power the United States over Canada 51-34 Saturday but defending champion Argentina routed host Chile 45-10 to stay atop the Americas Rugby Championship.
Argentina and the US Eagles each improved to 3-0, but the South Americans stretched their scoring difference margin atop the table from five to 23 points in the Six Nations-styled event.
If both teams win next week, when the US squad visits Chile and Argentina entertains Brazil, the title will come down to a US visit to Argentina in the March 4 finale.
Uruguay downed Brazil 23-12 in Saturday's other match.
In suburban Vancouver, Ryan Matyas made a 30-meter run for try and Te'o split two defenders after a stolen line out for another US try in the first five minutes before Shaun Davies added a penalty kick for a 15-0 Eagles lead.
Taylor Paris and Philip Mack answered with tries to pull Canada within 15-12 before Will Magie and Robbie Povey exchanged penalty kicks.
But Canadian captain Ray Barkwill was sent to the sin bin for an improper tackle in the 38th minute and the Americans struck seconds later, Tony Purpura driving over from the maul with Davies converting to put the US squad ahead 25-15 at half-time.
Povey missed the posts on a penalty early in the second half and the Eagles struck again with Canada still shorthanded, Magie's kick to the corner being knocked backwards by US winger Nate Augspurger and recovered by Te'o for a try and a 30-15 lead.
US captain Todd Clever scored a try when the maul drove over the line and Davies converted for a 37-15 lead.
Paris answered with an unconverted try for Canada three minutes later but John Quill added a try for the Eagles in the 65th minute and Davies converted for a 44-20 US edge.
Canada reserve George Barton added a try but Te'o responded to complete the hat trick of tries for a 51-27 US advantage. Canada's Admir Cejvanovic scored a last try to trim the final margin.
At Chile, Argentina's Bruno Devoto scored two tries and the visitors rolled to a 17-3 half-time edge and dominated the second half to keep the Condors winless.
Chile opened the scoring on Jorge Castillo's penalty, but Argentine captain Juan Cappiello answered with a try to his squad ahead to stay.
Argentina's Fernando Luna added a try to end the first half while Juan Cruz Gonzalez kicked a penalty. Luna and Gonzalez each kicked three conversions as well.
Devoto, Nicolas Solveyra and Bautista Delguy added second half tries for Argentina while Rodrigo Fernandez produced the only Chilean try.
Brazil jumped ahead 6-5 early at Uruguay, Moises Duque sandwiching penalty kicks around captain Juan Gaminara's unconverted try for the host Teros.
But tries from Ignacio Dotti in the 17th minute and Alejandro Nieto in the 40th boosted Uruguay ahead 15-6 at half-time.
Duque lifted Brazil within a converted try on a 43rd-minute penalty but Santiago Arata's try in response three minutes later boosted Uruguay's lead to 20-9 before penalties created the final margin.