Fixtures don't get much bigger than Boca Juniors versus River Plate.
And when Argentina's two biggest rivals are facing off in the final of the Copa Libertadores – South America's equivalent of the Champions League – it's doubly true.
To ram home the point that this is a big occasion, Boca fans made it a full house as their team took part in a training session at the famous Bombonera stadium in Buenos Aires ahead of this weekend's game.
Boca Juniors fans at a training session. A training session. There's such a thing as liking football too much. pic.twitter.com/9bptuD20qq — Rory Smith (@RorySmith) November 22, 2018
Indeed, such was the interest in the open training session that officials were forced to close the gates and put out a call for no more fans to make their way to the stadium.
Boca face River at their rivals' El Monumental stadium on Saturday, with the tie all square at 2-2 after the first leg.
It's the first time the two teams have met in the final of the Libertadores, but the tie is being played with no visiting fans allowed in the stadium for either leg – which may partly explain the huge interest in a training session.
Argentinian authorities have been attempting to tackle the problem of fan violence in the country – and the rivalry between Boca and River is one of the fiercest in world football.
🎥 @PipaBenedetto aparece en la pantalla de la Bombonera y los hinchas responden 🙌👏.#JugamosTodos 👊 pic.twitter.com/lSWDn2Zj99 — Boca Jrs. Oficial 🏆🏆 (@BocaJrsOficial) November 22, 2018
With fans denied a chance to go to the game instead packed in to the Bombonera on Thursday, footage from reporters showed the stadium physically shaking.
And at one point a supporter burst on to the pitch and was tackled by police, before being rescued from the situation by Boca forward Carlos Tevez.
The former Manchester United and Manchester City man shepherded the fan away from the officers and embraced him before introducing him to his team-mates.
The winners of Saturday's game will take home the trophy, a place in the World Club Cup and perhaps the ultimate in bragging rights.
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