Defensive shifts aside, I firmly believe that 99 mph heat at the letters -- instead of the 4th slider, in the same general location, in the 5th pitch of the at bat -- puts Merrifield away. I don't know if that was Giles' or Gattis' call there, but the pitch call had me shouting at the TV, in real-time. Hinch, in his post-game comments, did not seem happy about the pitch sequence, either.
Perhaps Giles gets Merrifield if he buries that last slider, but Giles was rushing to get warm in the pen, and it seemed a really bad spot to rely on a "feel" pitch.