Even though he's so laid back and doesn't look engaged, Matsushima was easily the best player of the four out there. His placement was excellent and plays within himself allowing Miwa to flourish, and poor Hayata was often on the receiving end of his loop bombs. If he keeps this up, why not consider him for the 3rd player to play doubles in XD and Men's Teams doubles in Paris.
I hope I'm wrong, but Hayata seems tired to me. I guess the thinking is there's just a few WTT tournaments left in the year, and she probably won't be entering Paris Trial #6 so she's got nothing to lose.