VAR makes unprecedented World Cup history as fans left baffled during USA's win over Paraguay

World Cup fans were left confused by an incident that occurred during the USA’s tournament opener against Paraguay – but there’s an explanation.

On Saturday (June 13), Mauricio Pochettino’s side got their campaign underway in style, with Paraguay’s Damian Bobadilla’s own goal handing the co-hosts the lead just seven minutes into their first Group D match.

Former Arsenal player Folarin Balogun doubled the USA’s lead on 31 minutes before netting his second and the home side’s third in first-half stoppage time. In doing so, he became just the second American to score twice in a World Cup match.

Despite the away side pulling one back through Mauricio with 17 minutes to go, Giovanni Reyna restored the USA’s three-goal buffer to make it 4-1 in second-half stoppage time, sending those inside the stadium home in a jubilant mood.

The win was the USA’s joint-biggest at a World Cup, having previously beaten Belgium and Paraguay 3-0 in 1930 when they went on to finish third in the tournament.

And despite the impressive performance from Pochettino’s side, fans on social media focused on a confusing refereeing intervention during the match.

READ MORE: United States equal feat last achieved by Spain 24 years ago with World Cup win over Paraguay

With the score at 3-0, former Fulham defender Tim Ream conceded a free-kick and was shown a yellow card by referee Danny Makkelie.

The free-kick was then taken before the Dutch official stopped play to look at the VAR monitor, overturning his call and rescinding Ream’s caution. He then showed Paraguay winger Miguel Amorim a yellow card for simulation, completely overturning his decision – something referees had not been able to do in relation to yellow cards before the tournament.

Refs are also allowed to overturn red cards issued to the incorrect player.

The incident was the first "mistaken identity" call of the tournament and it has left fans confused.

One said: "WHAT IS A VAR CHECK FOR MISTAKEN IDENTITY????"

Another added: "A good intervention but honestly I wouldn't call it 'mistaken identity'. They need to come up with a better name."

A third claimed: "The new 'mistaken identity' VAR rule gives VAR more power to correct situations where the referee books or sends off the wrong player. Previously, these errors could sometimes stand if play had restarted. Now VAR can intervene and tell the referee that the card has been shown to the wrong person. We need this in the PL!"

As a fourth commented: "Not sure why the ref needs to go to the monitor, slowing down the game yet again! VAR just needs to say free-kick the other way and give the player who dived the card! Common sense nowhere to be seen here."

While a fifth wrote: "Good. VAR finally being used as it should be. We see way too many yellows given when someone dives and cheats. At least this will finally start to cut some of it out."

The USA return to action against Australia on June 19.