Real Madrid CF and FC Barcelona clashed on the pitch at the Allegiant Stadium in Las Vegas on Saturday for a pre-season "El Clasico" as part of their tour of the United States. While the rivalry was intense on the field of play and in the stands, it was unusual to see that the entire audience appeared to be united in their dislike of Barcelona defender Gerard Pique.

Fans from both sides could be heard booing when Pique came in from the bench with about half an hour left in the match. It became very clear why he was getting a particularly hostile reception when the crowd started to chant "Shakira, Shakira" whenever he managed to touch the ball.

The Colombian pop star has a massive following in the United States, and they made their presence felt in Las Vegas. They also made it clear that they are not happy about the Barcelona player's recent split from the singer, with whom he has two young children.

The pair became a celebrity power couple after meeting at the 2010 FIFA World Cup in South Africa. Pique was part of the title-winning Spanish National Team, while Shakira sang the event's theme song.

Back in June this year, more than 11 years since getting together, they confirmed their separation. While they did not cite the real reasons behind their decision, Pique has often been accused of cheating.

None of the allegations have been confirmed, but that did not stop Shakira's fans from letting Pique know exactly what they think of him at the moment. Nevertheless, the Spaniard played on and helped his team secure a 1-0 victory over their rivals thanks to the lone goal from Raphinha.

Barcelona executives and even manager Xavi Hernandez knew that the controversy will follow Pique, and it has previously been reported that they want the player to make sure that his personal issues do not spill over into his work.

Pique has since expressed his anger at those spreading rumours that are damaging his reputation, and is vowing to take legal action if need be.

Shakira, who has sold over 60 million albums, had lived with Pique on the outskirts of Barcelona AFP / Bryan R. Smith