Looked to me that Rubin was red lining the ball, and it really paid off in the TB, Kyle playing a little bit within himself. If Rubin can keep that level up, he will be dangerous in the decider.
Going off will have helped Kyle more than Rubin though, I'd still expect him to come through a decider.
Kyle though has become a pretty good match player, markedly better in the last year, such that I am generally confident about him in extended 3 set matches and would have been if it could have been played to a conclusion yesterday.
Maybe though Rubin will not continue to such a standard on a fresh day.
Mr Rubin's strength is his movement - or at least that's my impression from the little I've seen of his play (not in this tournament). I didn't think he had much weight of shot at the time, but that may have changed. Think that Mr Edmund is probably more solid all around at present. And all of the other teens have lost in the second round (I think), so ....