Why Kevin De Bruyne's goal vs Real Madrid was not disallowed despite ball appearing to be out of play

Kevin De Bruyne scored a sensational equaliser for Manchester City against Real Madrid but the goal was not without controversy.

De Bruyne smashed in a strike past international teammate Thibaut Courtois, matching the thunderbolt Vinicius Jr conjured up in the first half to open the scoring at the Santiago Bernabeu.

But the leveller was shrouded in controversy as the ball appeared to go out of play during the build-up when Bernardo Silva stretched for Kyle Walker's slightly over-hit pass on the right flank.

Carlo Ancelotti immediately appealed and was shown a yellow card for losing his head on the touchline.

Images from beIN Sports using 3D technology showed that the ball had gone out but much to the anger of Real supporters, there was no intervention from VAR.

While other incidents such as handballs, penalties, offsides and red cards can be checked by VAR, the ball going out of play on the sideline cannot.

IFAB's website explains: "A video assistant referee (VAR) is a match official, with independent access to match footage, who may assist the referee only in the event of a ‘clear and obvious error’ or ‘serious missed incident’ in relation to: a. Goal/no goal, b. Penalty/no penalty. c. Direct red card (not second yellow card/caution), d. Mistaken identity (when the referee cautions or sends off the wrong player of the offending team)."

Former Arsenal manager Arsene Wenger, now FIFA's Chief of Global Football Development, confirmed that VAR doesn't have the technology to check whether the whole of the ball even if there is a chip in the ball - as used for Japan's winning goal against Spain in the World Cup.

But even with that, it's also emerged that VAR couldn't have overturned the goal anyway. Christina Unkel of CBS Sports reports that the ball going out was too far back in the phase of play for a VAR review to take place.

Real regained possession before Rodri won the ball back for City and the move finished with De Bruyne lashing home.

Page 141 of the game's laws states that "it may be necessary to review the attacking phase of play which directly led to the decision/incident" but the goal didn't arrive straight from the ball going out, hence the lack of VAR intervention.

Pavel Fernandez, speaking on Radio MARCA's 'Marcador Europeo' show, followed up with further details.

"VAR cannot review it, because the English team's attacking phase started later, after Camavinga had lost the ball, so VAR cannot review it that far back."

With proceedings all square, City and Real will go at it again next Wednesday at the Etihad Stadium in what promises to be a belter of a second leg.