Not looking good for him at all. Now it is already 17 - 8 for Zhao which leaves very little room for maneuver. Just one more frame needed which is impossible. If it were like 3 needed I wanted to place a bet on Williams since he is always playing to the end and more than ready to pounce on any weakness. And last session is a last session and place where Zhao hasn't been yet.
Now it feels and looks impossible to happen, but I'm glad that Zhao will probably be the winner. The guy has been in the tournament for almost a month, going through qualification and winning against 9 different players and styles of play. A marvelous feat to accomplish—and, as someone said, only 28 years of age.