The Wallabies have won a gritty and tense Test match described by two separate players as "bloody hard", securing a 27-21 win over Argentina.
Australia scored four tries to three in Sunday morning's clash in the mountain town of San Salvador de Jujuy, where the stadium sits more than 1,200 metres above sea level.
The Wallabies made a hot start with three tries in the opening 20 minutes, but had to show plenty of determination to hold off an Argentine fightback to secure the team's fourth Test win in a row.
The Australian forwards were excellent for much of the match, especially disrupting the Los Pumas' line-out in the second half.
Wallabies flanker Fraser McReight was named player of the match after an effort where he was a constant feature around the ball, including a crucial penalty won late in the contest with Argentina attacking inside the 22m.
"It was a back-and-forth sort of match," McReight told the host broadcaster.
"Argentina were very good. I felt like we were pretty poor in some areas, but [I'm] just really proud of the group and I'm happy we got the win over here."
The Wallabies were by no means perfect in Jujuy, with winger Max Jorgensen and flanker Tom Hooper each describing the match and conditions as "bloody hard" in separate interviews.
The Wallabies made a hot start with the opening two tries of the match. Hooker Brandon Paenga-Amosa finished off a lovely passage of passing between forwards to score in the seventh minute, then fly half Carter Gordon touched down four minutes later from close range after the Wallabies forwards pounded their way to the goal line.
Argentina struck back through fullback Geronimo Prisciantelli after a lovely backline move, but when McReight scored in the 20th minute, the Wallabies were in control at 19-7.
But Los Pumas wrestled back the momentum, and a sin bin with Wallabies winger Harry Potter for deliberately knocking the ball down in the 25th minute put the home side in the ascendancy.
Argentina number eight Joaquin Moro took a quick tap from close range and powered over the line to reduce the deficit to five points, but a penalty goal from Wallabies scrumhalf Ryan Lonergan gave Australia a 22-14 lead at the break.
Lonergan came off after just five minutes in the second half after making a desperate cover tackle to deny Prisciantelli a second try.
Los Pumas were denied a try due to a forward pass picked up by the TMO in the 48th minute, but loosehead prop Boris Wenger dove over three minutes later to reduce Australia's lead to one point.
But the Wallabies responded quickly, with a line break from centre Hunter Paisami putting Australia into the attacking 22m, and leading to Hooper reaching out a few plays later to give the Wallabies a 27-21 lead.
The Wallabies were on top as the second half wore on, but could not get the try to seal the game. Jeremy Williams knocked on while trying to score, then reserve scrumhalf Tate McDermott was held up over the line.
It kept Los Pumas in the contest, but the Wallabies' defence held firm in the final five minutes to secure the win.
"It was a very tough game. Everyone knows that coming over to Argentina is a bloody hard place to win. It's you against them, plus the whole stadium," Jorgensen told Stan Sport.
"It wasn't near perfect, we've still got a lot of work to do, but to come away with a win in Argentina is very good."
The win is Australia's fourth in a row, and maintains coach Les Kiss's perfect record after three Tests in charge.
Australia has leapfrogged Argentina into seventh on the World Rugby rankings, with both sides to meet next week in the second Test at Mendoza.
Follow all the live action from the first Test between the Wallabies and Argentina in the blog below.
