Argentina coach Jorge Sampaoli admitted his side were "emotionally broken" after conceding the first goal in their 3-0 defeat by Croatia on Thursday, which left their World Cup hopes hanging by a thread.
The two-time world champions need to beat Nigeria in their final Group D match on Tuesday and for other results to go their way to have any chance of reaching the last 16, after Willy Caballero's dreadful error allowed Ante Rebic to send Croatia on their way to victory and into the knockout stage.
"I am the one who needs to make the final decisions on these things. The key to our defeat lies with my responsibility," said Sampaoli.
"I had to devise a plan for this match. If I had set things up differently, things might have turned out much better. I don't think it's realistic to put the burden on Caballero.
"I thought that we were going to put a lot of pressure on Croatia and put a lot of pressure on them in their part of the pitch. But after they scored we were emotionally broken and we didn't have any footballing arguments to change the course of events."
Sampaoli only took over last year, becoming Argentina's fourth coach in as many years.
They only just qualified for the tournament in Russia, as a Lionel Messi hat-trick sealed victory in their final match of South American qualifying in Ecuador.
The Barcelona great has been a peripheral figure so far in Russia though, while his old rival Cristiano Ronaldo has scored four goals in two games for Portugal.
But former Chile boss Sampaoli says that Messi's struggles are more down to the quality of his team-mates.
"I think Cristiano is a great player, you can look at all he has achieved for his club and his country," said the 58-year-old.
"Right now we shouldn't compare these two players. The reality of the Argentina squad clouds Leo's brilliance. He is limited because the team doesn't gel with him as it should. We as coaches need to realise these things and try to deal with them and I'm the one that needs to accept it."
Argentina, who are looking to lift the trophy for the first time since the Diego Maradona-inspired glory of 1986, haven't been knocked out in the group stage since finishing behind England and Sweden in 2002.
But even victory over Nigeria may not be enough, especially after two late strikes from Croatia midfielders Luka Modric and Ivan Rakitic left them with a poor goal difference of minus three.
"When you don't have momentum it's very difficult to move forward. Some of the players didn't manage to play with my system," accepted Sampaoli.
"I'm very hurt by this defeat, but I probably didn't set up my team in the right way.
"We need to take advantage of this last (group) match, we need to fight for it and hope to get into the next stage."