The incident occurred at the Santiago Bernabeu during pre-match proceedings, which ironically featured a large 'No To Racism' banner being displayed across the stadium.

Television cameras captured the supporter appearing to make the offensive gesture from within the stands at the 83,000-capacity venue.

The club has moved swiftly to address the matter, with disciplinary proceedings now underway against the individual in question.

Security personnel at the ground swiftly identified the individual after footage appeared on the broadcast, removing them from their seat without delay.

In an official statement, the club confirmed it had "urgently requested the club's Disciplinary Committee to initiate an immediate expulsion procedure for the member who was caught on television cameras performing the Nazi salute in the area where the Animation Stand is located, moments before the start of the match between Real Madrid and Benfica."

The Spanish giants made clear their position on such behaviour, stating that they "condemn this type of gesture and expression that incites violence and hatred in sports and society."

According to The Athletic, performing a Nazi salute is not in itself a criminal offence under Spanish law, though it can become punishable if combined with other acts constituting hate crimes.

On the pitch, Real Madrid secured a 2-1 victory in the second leg to progress in the competition they have lifted on 15 occasions.

Vinicius Junior, the Brazilian forward, netted his side's second goal to confirm their passage into the knockout stages.

The Spanish club will now face either Manchester City or Sporting Lisbon in what promises to be a compelling last 16 encounter.

The match at the Bernabeu followed a first leg in Lisbon that was marred by allegations of racist abuse directed at Vinicius, with Benfica's Argentine midfielder Gianluca Prestianni accused of calling the Brazilian a "monkey" – a claim the player has denied.

Real Madrid goalkeeper Thibaut Courtois spoke out about the troubling incidents witnessed at the Estadio de Luz.

"There are the other things that happened in the stands that warrant stopping the match and ejecting those people," the Belgian said.

"We don't see what's going on in the stands; some people might see it, but it happens when we're focused on the game.

"There have to be other people in charge who take action."