Terrorists who committed an attack in Barcelona on Las Ramblas on 17 August were also reportedly seeking to attack the Camp Nou three days later.
It's said that detectives looking into the case found evidence on the phone of one of the cell members—Mohammed Hichamy—including research into match schedules, stadium access and photos of the iconic venue too.
"It is very possible that they wanted to attempt the same as the attackers in Paris that attacked the Saint Denis stadium in the middle of the match of French national team," a source told El Periodico, making reference to the terrorist attacks on the Stade de France in November 2015 during France's game with Germany.
It's added that the owner of an official Barcelona store reported that at least two members of the cell had been in the shop buying merchandise.
As noted by BBC Sport, players at the match remembered those who had died in the attack in the Catalan capital, while additional security measures were put in place on the day.
Supporters chanted "We are not afraid" during the game, and a banner among the 56,480 fans in attendance read "No-one can ever break us."
The attack in Las Ramblas saw a van driver kill 13 people and injure many more after driving the vehicle into crowds.