FC Seoul began their AFC Champions League Elite campaign with an emphatic 3-0 home victory over Buriram United on September 30, 2025. The dominant performance at the Seoul World Cup Stadium sent a strong message to the rest of the group about the Korean side's intentions this season. Seoul took the lead through a powerful header from a corner in the first half and never looked back. They added two more goals in the second period, showcasing their superior attacking quality against the Thai champions. The comprehensive win gave FC Seoul an ideal start, topping the group on goal difference, while leaving Buriram with a significant setback. The Seoul manager was delighted with his team's intensity, and the Buriram coach conceded his side was outclassed on the day.