Washington - Argentina scored eight tries in a 52-15 victory over Chile on Saturday to go top in the Americas Rugby Championship with the same eight points as the United States, who beat Canada 30-22.
Argentina's bonus-point win at Bicentenario stadium in San Juan, Argentina, included four tries from Joaquin Paz and two from Sevens standout Segundo Tuculet, younger brother of Pumas star Joaquin Tuculet.
Santiago Portillo and Rodrigo Etchart added one apiece for Argentina, who aren't fielding a mix-and-match squad for the six-nation tournament conceived to give top North and South American rugby countries valuable matches.
The United States and Argentina played to a 35-35 draw in their tournament opener a week earlier, and the United States remained neck and neck with the Pumas with their victory over Canada in Austin, Texas.
Todd Clever produced three tries in eight minutes in the second half to fuel the United States to victory at the Dell Diamond baseball ground.
Gordon McRorie booted 15 points for Canada, who saw Dunan Maguire score his first Test try.
McRorie pushed Canada's 12-10 halftime lead to 15-10 shortly after the interval, but then Clever erupted.
The Newcastle Falcon powered over for his first try of the night in the 57th minute to pull the Eagles level.
He was in again four minutes later giving the hosts their first lead at 20-10.
After another driving maul had been established, Clever this time snuck out the back and plunged over to secure his hat trick in the 65th minute, with Niku Kruger's conversion making the US lead 27-15.
Canada responded as Maguire took a pop pass off the floor from fly half Gradyn Bowd before accelerating past the USA back line to grab his first test try. Andrew Ferguson added the conversion.
With Canada attempting to force turnovers they were eventually penalized and Kruger stepped up to slot home a vital three points to secure a 30-22 win.
Clever, a veteran presence on a US side that included 10 new caps, said the Eagles felt they could turn the tide even when they trailed at halftime despite Chad London's first-half try.
"We had a chat at halftime," he said. "We felt like we were quicker and we could put pressure on them. We wanted to keep our foot on the pedal."
Canada's interim coach Francois Ratier, meanwhile, said small mistakes were costly for the team that opened the competition with a 33-17 win over Uruguay.
"We had a few moments where we lacked concentration at some key moments," interim head coach Francois Ratier said. "Missed tackles, penalties when we had the momentum, these little mistakes made the big difference."
Uruguay's 33-29 victory over hosts Brazil in Sao Paulo on Friday had kicked off the second round of action.
The competition will continue for five weeks, with a champion crowned on March 5.
The third set of matches next weekend will see Uruguay host Argentina, Canada host Brazil and Chile host the United States.