Well, as an tennis player myself for more than 15 years I have to say that I agree with Neru. In reality nobody in a team competition cares if the player from the other club held back or just played bad. It simply doesnt matter. Because on the court everything matters what happens right there: your mood that day, the food you have eaten on breakfast, how much water you have consumed and will before and during the match, the surface, the weather, a little bit of luck; the list is almost endless. But one of the things that doesnt matter is the past or what might happen next day. Of course your potential matters, but if you cannot use it at its fullest and your opponent can and thus wins, he was the better player THAT day! Do you think the other team cares if I say "hey, I maybe lost today 2-6 1-6, but I could have beaten him 6-0 6-0 if I wanted" ? They wouldnt even laugh.
I too think Federer has more talent, but Nadal wins and thats why he is the better player. If you chose to bet your money on an outcome you may go by potentail.
And if Sanada would have lost because of his stubborness, Tezkua would have been the better player. And "better" just means anything, even attitude and how much you care for your teams sake. If he chose the wrong attitude because he must by all means crush Tezuka and loses because of this its his own fault and hes the worse player.
Of course thats only goes by reality... if you now say "hey, its a manga and thats why [....]" you could actually be right

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