Barcelona immediately showed off their quality on the ball as Lamine Yamal found Pedri inside the box with a backheel pass before the midfielder shot wide. The 18-year-old then showed exactly why he is a Ballon d'Or candidate as he glided through the FC Seoul defence before firing a shot that rebounded off the post for Robert Lewandowski to tap it in for his first goal of the season. Just minutes later, Yamal doubled the Catalan side's lead with a spectacular long-range strike after another mazy run.
That did not turn out to be a killer blow, though, as Seoul fought back with two goals in the space of 20 minutes. The comeback began when Yamal lost possession cheaply near his own box and Cho Young Wook scored with a well-taken finish. Seoul's second goal came on the back of a delightful Lingard flick, which built up towards a brilliantly worked goal that saw Yazan Al-Arab fire past Barca goalkeeper Joan Garcia.
Yamal then decided to turn it on once again in injury time of the first half to put Barca back in the lead after Dani Olmo's delightful through ball. The Blaugrana's new No.10 sat a Seoul defender down with a clever dummy before unleashing a thunderous shot to double his goal account.
Head coach Hansi Flick rang the changes for the second half, with new loan signing Marcus Rashford looking lively right from the off. However, it was Andreas Christensen's spectacular long-range strike that opened the floodgates for Barca in the 55th minute. Ferran Torres and Gavi both followed up with goals of their own before FC Seoul grabbed one back through Han-min Jung. Torres then had the final say as he got on the end of a deft pass from Rashford to close out a thumping 7-3 victory for Barca.