George Duke wrote on Fri, Sep 19, 2014 10:46 PM UTC:
Where does Black go wrong? Let's guess it's beyond their strict
memorization at around Move 9 ...Q-c7. Still several more moves are pretty
routine.
http://www.chessgames.com/perl/chessgame?gid=1693032.
How about saying error by Black standing out is
14 ...Q-b6, where instead 14 ...Q-h5 looks pretty fearless. The way it actually went, after Castling, 19 ...fe6, and Black has awkward doubled Pawn.