Lionel Messi praised Argentina's work ethic after scoring the winner on his return to international football as Brazil were beaten 1-0 in Riyadh.
The 32-year-old was banned for three months by CONMEBOL after criticising the South American governing body during this summer's Copa America, both after a semi-final loss to Brazil and a third-place play-off win over Chile in which he was sent off following an altercation with Gary Medel.
However, the Barcelona forward made a triumphant return as he scored the only goal of the game in an international friendly in Saudi Arabia.
"At the beginning we tried to play, we made a few mistakes and they created some chances," Messi told the Argentinean FA's official website.
"In the second half we improved a lot.
"I think this system defensively gives us a lot. It's good that we can play in several ways.
"When you win, you work with peace of mind, it is very positive for what is coming.
"We all ran a lot – it's what we had to do."
Gabriel Jesus hit a tame effort straight at Esteban Andrada after seven minutes, but moments later earned a penalty when he was fouled by Leandro Paredes in the area.
The Manchester City striker took the spot-kick, only to fire wide from 12 yards in the 10th minute.
Two minutes later Argentina were awarded a penalty of their own when Messi was tripped by Alex Sandro.
Liverpool goalkeeper Alisson Becker saved Messi's spot-kick, but the Barcelona forward was left with a simple task to tap in the rebound.
Messi could have doubled his tally a minute before half-time when he burst clear of the Brazil defence, but Alisson stood firm to save his low effort.
Jesus and Willian both failed to work Andrada as Brazil sought an equaliser after the break, while at the other end Messi's 66th-minute free-kick had to be tipped over by Alisson.
Lautaro Martinez and Nicolas Otamendi both wasted late chances to make the game safe for Argentina, whose win represented a first against their arch rivals for more than two years.
Argentina manager Lionel Scaloni added: "I liked the second half.
"We made changes because we wanted to prepare for the tests that are coming.
"The team responded and played really well."
Brazil coach Tite felt the game's deciding spot-kick should not have been awarded.
He told Brazilian media outlet Globo Esporte: "I did not see clearly, I know there were comments that it was not a penalty. For me it was not a penalty."
