Beaten finalists at the hands of Germany four years ago, Argentina failed to convince in qualifying for this year's tournament in Russia, where they have drawn 1-1 with debutant minnows Iceland and been taken apart by Luka Modric and Ivan Rakitic in Nizhny Novgorod on Thursday.
La Albiceleste have just one point ahead of a final match of Group D against Nigeria in St Petersburg, and face the prospect of bowing out at the first hurdle for the first time since 2002, in what could be Lionel Messi's last appearance on football's biggest stage.
"I don't know about shame, but I definitely feel pain," Sampaoli told a news conference at Nizhny Novgorod Stadium.
"It's been a long time as a coach since I've been through this experience and it's much more painful when I'm wearing the jersey of my country.
"Our plan for this match didn't work out and we need to see what happens and put everything we have into the last opportunity to fight and give it out all. We have no other alternative.
"There's pain because we weren't at the level that the Argentinian people expect of us."
— Selección Argentina (@Argentina) June 21, 2018
Asked what his message would be for the country's fans, Sampaoli said: "I would beg for their forgiveness, especially those Argentina supporters who made such a great effort to be here.
"And I repeat what I said, I'm responsible. I was just as dreamy-eyed as any fan before. So I'm hurt.
"I did the best job I could and I quite simply did not find a way to give them what they wanted."
Photo Getty Images. Caption: Argentina coach Jorge Sampaoli