Lionel Scaloni says he is "not here to criticise his players" after they suffered a shock 2-1 defeat to Paraguay in World Cup qualifying.

Lautaro Martinez had given Argentina the lead in the 11th minute – his powerful shot past Roberto Fernandez was initially ruled out for offside before a VAR review overturned it.

However, Paraguay were soon back on level terms. Gustavo Gomez rattled the crossbar with a diving header from a corner, but they regathered possession and pulled level with a sublime overhead kick from Antonio Sanabria 19 minutes in.

Two minutes into the second half, the hosts completed the turnaround through Omar Alderete, who met Diego Gomez's precise free-kick to nod in from close range.

Rodrigo De Paul arguably should have equalised for Argentina with just over 20 minutes to go, but under pressure, sliced over from close range, with the visitors unable to salvage a point.

It was a third defeat in World Cup qualifying for the Albiceleste, who remain top of the standings with 22 points, and Scaloni chose to focus on the positives.

"I'm not here to criticise my players; I'm here to support them," Scaloni said. "We knew it was going to be a tough match. We're here to move forward.

"In the first half, we played a good game, but the first action at the start of the second half made everything more difficult. We have to congratulate the opponent, who defended very well.

"I don't know if they found the antidote [to beating Argentina]. We're hoping to get back on the positive path.

"The team always tries and stands tall. That's what's important: never giving up on the game and always having the desire to compete."

Paraguay are sixth in the table, having extended their unbeaten run to six matches, which also includes a win over Brazil.

They had to dig deep, having only 23.2% possession throughout the game, though they had eight shots to Argentina's nine and scored with both of their efforts on target.

Head coach Gustavo Alfaro is yet to lose a game since taking over Paraguay after the Copa America, and he hailed his team's resilience.

"With the rebelliousness of these players in the face of adversity, I have no doubt that we will get there. When the predisposition is so great, time is secondary," he said.

"They were fantastic points, very difficult. It is difficult to take a point from Argentina."