Napoli is always one of the toughest away days in the Champions League.It was the turn of Barcelona to make the daunting trip to the San Paolo Stadium this week, emerging from the first leg of their round of 16 clash with a 1-1 draw.Napoli had already claimed the scalps of Liverpool and Genk at home in Europe this season, drawing with Red Bull Salzburg, and rushed into a 30-minute lead against the Blaugrana.Dries Mertens became the club's joint all-time top scorer with a stunning curled effort, only for Antoine Griezmann to spoil the party after the break thanks to a predatory finish.And despite Arturo Vidal receiving his marching orders for two yellow cards, Barcelona managed to bubblewrap their away goal and will return to Camp Nou with the scores level pegging.

Napoli's home support

In Barcelona's defence, it's no small feat and especially when you consider their capitulations against Liverpool and AS Roma over the last two seasons.

But the resilience of the Napoli squad wasn't their only challenge on the night, because the partisan atmosphere that home supporters create can be even more intimidating.

We've all seen the viral video of the Napoli stadium announcer screaming 'Gonzalo Higuain' to rapturous replies to get a gauge of the Naples support.

Champions League anthem

And the San Paolo faithful, of which they were approximately 45,000, arguably went one better during the Champions League anthem on Tuesday night.

As soon as Tony Britten's iconic tune reached its dramatic conclusion, the entire Napoli contingent completely overwhelmed the music by bellowing 'The Champiooooooooons' in harmony.

Broadcasters BT Sport promptly uploaded the clip and 1,500 retweets - as well as 9,200 'likes - at the time of writing suggests it went down a treat. Check out the footage down below:

Sheesh. It's so loud it sounds like audio editing.

Just as the anthem is coming to its conclusion... BAM.

It's not the first time that Napoli have hijacked the Champions League anthem, doing so before the Liverpool game and following it up with a 1-0 victory.

However, there was to be no such win on Tuesday night and Barcelona must take it as a positive considering the accusations lodged against their nerves on the big stage. 

After all that's happened for them in Europe recently, it isn't hard to imagine beads of sweat forming on a fair share of foreheads when 'The Champiooooooooons' reverberated around the stadium.

But fortunately for Barcelona, they're still well in the running to be, well, the champions.