How Hansi Flick & Barcelona players reacted to 'wrong' offside in La Liga defeat

"It was not our day," Hansi Flick lamented after a rare defeat for Barcelona.

The rampaging La Liga leaders had a run of seven consecutive victories - in which they had scored 27 goals - brought to a screeching halt with a 1-0 loss away to Real Sociedad on Sunday night. The record books will show that Barcelona were denied a single shot on target - the first time that had happened in a league game since September 2014 - however, Robert Lewandowski had the ball in the net after 13 minutes.

The Pole's first-half strike was ruled out for offside after a lengthy VAR review. That decision knocked Barcelona out of an early rhythm which they never recovered and has led to widespread declarations of injustice and technological manipulation.

Here's everything you need to know about the the most controversial decision of the season thus far.

Despite lining up without the injured Lamine Yamal, Barcelona started brightly at Real Sociedad's Anoeta. Lewandowski was first to react to Frenkie de Jong's blocked shot, wrestling Nayef Aguerd out of the way before hooking a clever effort beyond Alex Remiro in the 13th minute.

Lewandowski and his teammates had celebrated what would have been the Pole's 20th goal of the season before referee Guillermo Cuadra Fernandez belatedly blew his whistle to signal for an offside. The officials had decided that Lewandowski's toe was closer to goal than any part of Aguerd's body at the point of De Jong's shot, thereby ruling the Barcelona forward offside. However, the initials replays didn't quite support that conclusion.

How did the referees decide that Robert Lewandowski was offside?

During the half-time interval, Flick stormed towards referee Cuadra Fernandez demanding an explanation for the disallowed goal. "You say: it's not offside. What can I do?", the official shrugged, as quoted by Mundo Deportivo. When Barcelona's manager continued to fruitlessly argue his case, Cuadra Fernandez explained: "If the VAR says it's offside, why would we make it up?"

Even though the on-pitch official was the lightning rod for Barcelona's protestations, he didn't make the final decision. Even VAR Carlos del Cerro Grande plays a secondary role in offside calls given that La Liga employs semi-automated offside technology (SAOT).

This advanced system captures 29 data points on each footballer 50 times per second, providing an instant snapshot for any potential offside call and removing the need for the laborious line-drawing which the Premier League still uses.

The point of debate at Anoeta on Sunday night revolves around the positioning of each player's feet. To many observers, La Real's Aguerd appears to have his boot closer to goal than Lewandowski's.

The Technical Committee of Referees (CTA) defiantly insisted that there is no chance of the technology mistakenly confusing Lewandowski's boot for that of Aguerd as SAOT uses ten more cameras than are available for the broadcasters.

Hansi Flick was not impressed with the decision / Juan Manuel Serrano Arce/GettyImages

After his mid-match rant at the official, which had to be halted by his assistant coaches pulling him away, Flick still wasn't happy with the disallowed goal. "We started well and we scored, but it was wrongly ruled out," the manager told Barcelona's official website. "I told the referee that it was a bad decision, that it wasn't Lewandowski's foot. But we have to accept it."

Flick didn't use the contentious call as an excuse for the lacklustre 77 minutes which followed. "We could have played better," the German coach admitted, "like we did in the first few minutes, but we couldn't maintain the dynamic and we didn't create enough chances.

"We connected well, with possession, but then we started to struggle and with that they scored. In the last third, we weren't making the right decisions."

How Barcelona's players reacted to Robert Lewandowski's disallowed goal

Immediately after the defeat, Barcelona's players questioned the decision without being quite as defiant as their head coach. Goalkeeper Inaki Pena warned: "If there is such a clear and serious error, we hope that La Liga acts because that is what the guidelines are for. If it was a mistake, let it be proven, let it be investigated and let it act."

While midfielder Marc Casado urged the league to "look at the offside". "It would be serious if they disallowed a goal that is legal."

Raphinha quickly took to social media post-game to voice his opinions on the decision. The in-form forward posted an image of cartoonishly long shoes beneath the match footage of the offside call to mock the ruling.

This fascination with the size of Lewandowski's boots - he wears wears an EU 44 (UK 9.5, US 10.5) - was taken up by Barcelona's in-house commentary team during the match. One of the club's broadcasters joked during the game: "He has a size 70 foot!"

His co-commentary couldn't help but laugh in a mixture of shock and disgust. "They put Krusty the Clown's shoe on him, I think it's sensational, they could have also lengthened his nose and banned him for three games for touching it."

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