The South America Six Nations will be decided next weekend after Argentina XV and Uruguay XV claimed bonus-point victories against Chile and Brazil respectively to remain unbeaten after the first two rounds of the region's premier competition.

Both teams are tied at the top on a maximum 10 points, but Argentina XV have yet to concede a try and have scored 21 and their points difference is significantly superior – 128 compared to Uruguay XV's 26.

Colombia, having recovered from a heavy loss to the Argentina XV in round one with a 43-13 victory against Paraguay, could finish third with a win in their first visit to Montevideo. Argentina XV will travel to dethroned champions Brazil and Paraguay host Chile.

Colombia 43-13 Paraguay 

Once they recovered from the shock of a seventh-minute yellow card, Los Tucanes went on to execute their game plan to perfection in a dominant performance against Paraguay at the Cincuentenario Stadium in Medellín.

Captain José Manuel Diosa converted his own try and four others in a win that lifts Colombia to their highest-ever World Rugby Ranking of 33rd.

“We analysed Paraguay’s loss against Brazil and focused on how to generate ball possession,” explained Diosa, who switched from centre to full-back for the must-win match.

“It was like a game of chess; we did everything we trained on during the week and the scoreboard shows we were the better side in every aspect of the game.”

The opening half was tight and finished 12-6 to Los Tucanes after centre Juan Davila Metaute scored a brace of tries – the first while prop Yani Perez was in the sin-bin, one of which was converted by Diosa. Winger Diego Argana supplied all of Paraguay's points through two penalties.

Knowing the hard yards had been done in the first half, Colombia stepped up a gear against a tiring Yacarés outfit in the second half to score four more tries and only concede one in reply. 

Emanating from a stolen lineout deep inside their own territory, Colombia's third try came just two minutes after the restart and was scored by winger Arley Urrutia. 

Colombia had to wait until the hour mark before getting the bonus-point try, despite Paraguay having gone down to 14 men after replacement Gaston Navas picked up a yellow card.

With the score at 26-6, Paraguay scored their only try of the match through full-back Horacio Aguero but Diosa's converted score and a drop goal and a sixth try from Diver Cebbalos ensured the home side finished on top.

“It could have been a bigger win as we should have scored two or three more tries,” reflected Diosa, whose 18-point contribution came from a try, five conversions and his second drop goal in as many weeks.

Argentina XV 55-3 Chile 

Winger Manuel Montero scored a hat-trick of tries for the Argentina XV who are now in pole position to win the South America Six Nations.

Argentina XV dominated in every aspect of play to run in nine tries, with Montero getting them off to flying start with his first score after just two minutes.

Full-back Tomás Albornoz then scored tries either side of Benjamín Baraona's penalty for Paraguay before Montero crossed again after blasting through several would-be tackles. Argentina XV closed out the half with a penalty try after their dominant scrum proved too hot for Los Condores to handle.

Montero had his hat-trick within seconds of the second half, Albernez setting up the opportunity with the original line break. 

Forwards Nicolás Sbrocco and Javier Corvalán added their names to the scoresheet before replacement back Tomás Cubilla pounced on a handling error to score with two minutes remaining.

Still, head coach Ignacio Fernández Lobbe feels there is room for improvement ahead of their trip to Brazil.

“We failed to keep the intensity throughout the game and some of the things we practiced did not work for us,” said the former Puma, who hopes his side can avenge last year's shock defeat to Brazil.

“One of the good things about rugby is that you always have a return game, a chance to put things right. We have ours on Saturday.” 

Brazil 19-38 Uruguay XV

Uruguay XV enjoyed a brilliant comeback victory against the reigning South American champions to stay in the hunt for the title.

The visitors found themselves 12-0 down on the scoreboard in the early stages, the partisan home crowd inside the José Liberatti Stadium celebrating wildly as last week's hat-trick hero Daniel Lima and captain Yan Rosetti got Os Tupis off to a brilliant start.

It could have been even worse for Uruguay XV had Brazil not spurned a couple of other good opportunities. 

Uruguay XV dug in though and a brilliant team effort, finished and converted by Federico Favaro, got them back on track. Further converted tries from Germán Kessler and Felipe Aliaga, either side of an individual effort from Os Tupis' captain and full-back Daniel Sancery, led to a half-time score of 21-19 to the visitors.

A low-key third quarter only produced three points from the boot of Favaro but Uruguay finished with a flourish to score two more tries through Agustín Della Corte, from a charged down kick, and replacement back Manuel Blengio with Favaro kicking his second penalty in between.