Tottenham Hotspur's Heung-Min Son said he lost sleep and felt "empty" during South Korea's 2019 AFC Asian Cup campaign, which ended after they lost 1-0 to Qatar in the quarter-finals on Friday.
Son said he could have prepared better for the tournament, which began amid a congested period in his club season, per Sky Sports:
"I wasn't fully prepared. I felt physically empty. I feel so sorry to have let down my team-mates, coaches and the fans. I would rather not speak about it really but I haven't felt right physically.