When Dutch referee Danny Makkelie stopped the game between the United States and Paraguay in the early stages of the second half after Antonee Robinson headed the ball out of the home penalty area, it was not initially clear why.

It turned out he was being sent to the pitchside monitor by Spanish video assistant referee (VAR) Carlos del Cerro Grande to review his decision to give USA skipper Tim Ream a yellow card for fouling Paraguay forward Miguel Almiron.

Almiron had not been touched, so Makkelie reversed the caution and gave it to the former Newcastle player instead.

It seemed as though the tweaked 'mistaken identity' rule was being used and was welcomed by many watching.

"Good spot and the right decision I may add. That's the main thing," said BBC commentator Danny Murphy. "Any adaptation of the rules that means diving gets punished is good."

Except it might not have been the right decision.

Mistaken identity can only be used for a specific incident, when the referee "has clearly penalised the wrong player", according to the wording of the International Football Association Board (Ifab). "The offence itself cannot be reviewed." Mistaken identity does not appear to cover an opposing player incorrectly being booked when someone has dived.

Well-placed sources have told BBC Sport Makkelie's decision was wrong, even if it felt right.

World governing body Fifa is yet to clarify the situation.

Former England defender Phil Jagielka is all for diving being punished.

"I'm a defender, so I don't mind," he told BBC Sport.

"Stuff like this, it's got to help. Tim Ream gets booked - he could end up getting sent off, and he's physically not touched someone.

"It's hard for the referees to get every decision correct. If something like that does happen, where there's obviously not been contact and it's been simulated and the referee has fallen for it, why not reverse it?

"The only thing is, what happens if I touch you a tiny bit and then you dive? You can't reverse it, because I've touched you, even though my touch hasn't made you collapse and fall over. Where do you draw the line?"

The Ifab and Fifa have introduced so many law changes for this World Cup, perhaps it should come as no surprise referees have come unstuck.

On face value, overturning Ream's yellow card to book Almiron for diving seemed a sound decision. It is the kind of VAR intervention fans can get on board with.

Except it was never the intention - and it seems to be wrong in law and VAR protocol.

Across the briefings over the past six months, head of referees Pierluigi Collina did not reference diving in relation to mistaken identity.

Collina has been so eager to prevent injustice that lots of similar checks have been added. To corners, to free-kicks and second yellows to name three.

In a search for perfection, we have instead ended up with confusion.

This is why it was wrong.

Collina introduced the law change around cautions being issued to the wrong player for the same offence because, in the final of Euro 2016, France's Laurent Koscielny was booked for handball, but the handball was by Portugal striker Eder. Same offence.

In the USA game, a foul by Ream was corrected to simulation by Almiron. Different offences.

Then there is the fact that the VAR review happened after the referee had very clearly intentionally restarted play with a Paraguay free-kick.

Under VAR protocol a review cannot happen after play has restarted.

What would have happened had Paraguay scored from the set-piece?

It seems highly likely Fifa will have to issue a clarification about this, otherwise fans are going to expect the VAR to intervene on diving.

All in all, it is a mess.

When Fifa announced in December it was introducing mandatory three-minute hydration breaks "regardless of weather conditions", few took much notice.

After all, it was anticipated temperatures would be high and player welfare is a priority.

So far, heat has not been an issue. Three of the opening four games were played at temperatures just above 20C. Canada's draw with Bosnia in Toronto - which was played in the afternoon - was higher at 26C.

It was similar to temperatures in Chicago last July, when West Ham played Bournemouth in a Premier League Summer Series match and then Hammers boss Graham Potter - now in charge of Sweden, who open their World Cup campaign against Tunisia in Monterrey on Sunday night local time (Monday, 03:00 BST) - was dismissive of the hydration breaks used then.

"I have no idea why there was a water break," Potter said at the time. "Somebody needs to tell me why that was the case. I assumed there wasn't going to be one because I came out with a jumper."

Speaking before his side's impressive 4-1 win against Paraguay in Los Angeles, USA coach Mauricio Pochettino was also dubious about the benefits.

"I don't like it," he said. "I only like it when the conditions are extreme, but when the conditions are good, it is unnecessary."

Coaches are allowed to offer tactical instructions. Ifab rules state the use of electronic devices is permitted "where it directly relates to player welfare or safety or for tactical/coaching reasons", stipulating only that the device must be small.

However, there may be another benefit - a financial one.

It has been noticed broadcasters are using the gaps to run commercials, although US network Fox has been criticised for not returning to the action before the opening game between Mexico and South Africa restarted.

"They're doing it for safety reasons, but in effect we're playing quarters now, which I find strange," said Jagielka.

"It's literally play for 25 minutes and stop for little bit of a break.

"I understand it - there's going to be a lot of football, a lot of minutes. You need to prevent people pulling muscles and allow them to get the hydration in.

"But does it need to be three minutes? How long does it take? It could be a minute."

Whatever the precise reasons for the breaks, and whether they are needed physically or not, Jagielka feels coaches can derive huge benefits from them, especially if a team is underperforming.

"That three minutes could be massive," he said. "If your team's not doing well, and it's a loud stadium, it's nigh on impossible to get messages on [to players].

"If you're a manager or coach, you'll be delighted because you can get the lads together and be quickly firing as much information into them as possible.

"I'd say it's more important than half-time. Obviously, at half-time you might be able to show things on a camera or have a bigger view of tactically what's going on, but, especially if your team's not doing great, you could literally turn a game around in that break with what can go on in those three minutes."