Argentina captain Lionel Messi has said his side need a "drastic change" if they are to qualify for the 2018 World Cup after Edgardo Bauza's men suffered 3-0 loss to Brazil on Thursday.
Goals from Philippe Coutinho, Neymar and Paulinho secured a memorable win for Brazil over rivals Argentina in Belo Horizonte.
The result sees Brazil top of CONMEBOL qualifying by a point, while Argentina are sixth in the 10-team standings, with the top four automatically qualifying for the tournament in Russia in two years' time.
Barcelona star Messi told Ole newspaper: "We need to change our mental approach. If one is not mentally well then the legs don't respond.
"We need to change this s---ty situation. We didn't expect this result. It could have even been worse. We weren't able to react.
"We must improve a lot. We can't repeat what we've been doing up to now because we will not come out of this situation. We still depend on ourselves but we cannot give away points, especially at home. We need a drastic change."
Of the match itself, Messi said: "We're upset with the result, with the game, and unfortunately, we've lost another.
"Up until their first goal, we felt we were both pretty even. Everything was fine. But after the second it hurt us a lot.
"The second goal finished us off. We were disorganised, we started to get desperate and there were large spaces that they got through with their speed.
"But that's it, we have to focus on facing Colombia and be aware that there are many thing we need to change so that this situation changes."
Argentina are next in action at home to Colombia on Nov. 15, and Messi has called on the nation's fans to get behind the team.
He said: "I hope the people in San Juan have patience. That affects us. I watched on TV the game in Cordoba [Argentina's home loss 1-0 to Paraguay on Oct. 11] and I could see that the players were booed and insulted. That does not help. We need to be united. We need to feel that we are the hosts.
"They have to understand that we need to do it together. We are the first to want to win and get results. When those around you are not behind you, you notice that.
"We have a few days to forget and prepare the next one. It needs to be different to that [performance] of today. We know we are going to be punished but we need to be strong to come out of this situation.
"There are many games left and we are not thinking about missing out on qualifying. Winning the rest of them we will be back in contention. We must be positive because we think we will get there but we need to change a lot."