|zanzibar: (Pre-move 14.Be3-g5)
click for larger view
Engines don't play moves like the 14.Bg5. But it puts the whole game on the line for White.
Unfortunately for Zukertort, the sacrifice can't be accepted by Black.
Black does have an amazing defensive move which is very hard to spot, 14...Bxd4!
It clears g7 for the king, wins a pawn, and offers the bishop f2 as sanctuary via the check (a ricochet maneuver). That tempo gain means the c6-knight, which appears to be overloaded, isn't.
The more obivous 14...Qd7, unpinning the knight also works. Of course, Zukertort accepting the bishop-sac means going out in style.
Although, after 20.Rxf8 Black could have resigned right there. Or maybe finished with the more entertaining ending by accepting the proffered Q-sac on the next move:
21...Qxg7 22.Re1+ Kd2 23.Re2+ Kc1 24.Rf1#