I think it's rude. If I were there and wanted to convey same idea, I would say
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I want to cheer them up, but to be honest, I think it's going to be a little difficult right now. It's because I'm mentally too tired from a tight schedule, and I've lost to them three times in a row in the league and in the Masters, so I feel more resentful myself that I can't win against them than I'm rooting for them. But on the other hand, it's a lie if I don't want them to hit the top. There are Jingg and f0rsaken who are close to me, and I think it would be nice to see them achieve their goals for some reason. And if they win, I think they can win something better when they meet them again.
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It would be more clear both to express his current emotion and to support them.