The South Korean forward was devastated to lose 4-3 to Chelsea at home on Sunday.
Despite being 2-0 up, Spurs went 4-2 down before Son grabbed a late consolation.
Post-game, he stated to Sky Sports: "It's very disappointing. I don't know what to say at the moment. We did such a good game in the first half an hour. We conceded very sloppy goals. It feels like we lost because of these small details. On such a big stage, you need to step up and score in these moments. I feel like I let the team down and I feel very sorry for the team.
"We can't concede goals like this. We can't dive into this situation. I can stay here all day talking about the mistakes but I'd rather blame me with the chance and I'd rather take the blame. I had a bit of a different thinking when I was running to the ball. I'm also human and I miss. I feel the pain because it's such an important moment of the game. The team tried.
"We got to stick together in such difficult moments, it's very important and it's why we need big support. The players are very young and they need support more than before and more than we had. The fans were always supporting amazingly but I think it's time the players also need to step up. We need some big support and big cheering up."
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