A couple of weeks ago I was spectating at an active tournament at the Milwaukee Market Creamery on Hornby Street in Vancouver. One of the games attracted particular attention when it arrived at the position shown in the diagram.
White, an A-class player, had uncorked the Blackmar-Diemer Gambit against his Expert-class opponent, and had sacrificed the exchange to speed up his attack. His last move was Ne2-g3, bringing his knight into action. His opponent had replied with ...Rd8-d5, trying to deal with White's massed pieces.
It was now White to play, and White was thinking.
Here I recalled something that Emanuel Lasker once wrote: there are certain moves you either see right away, or you do not see at all.
I remembered this because I could see a forced win for White, but White was still thinking.
After what seemed like forever he picked up his c-pawn and played 1.c4? Black immediately replied 1...Rf5!, returning the exchange and effectively killing off White's attack. White made a few more attacking gestures but was eventually was forced to capitulate.
In the diagram position White has a very powerful follow-up to his previous move:
1.Nh5!
Black is forced to take this knight because he is threatened with mate on g7 and 1...Qf8 doesn't help.
1...gxh5
This has the drawback of opening the b1-h7 diagonal for White's bishop, but taking with the knight is even worse: 1...Nxh5 2.Qxh7+ Kf8 3.Qh8 mate.
2.Bxh7+ Kh8 3.Rxf6
Black is now completely helpless. His next move is as good or bad as any other.
3...Rxg5 4.Bg6+ Kg8 5.Qh7+ Kf8 6.Qh8 mate.
We've already quoted the World Champion Lasker, so let's finish off with a quotation from his successor Jose Raul Capablanca:
“...the games of the great masters are not played by single moves, but must be played by concerted plans of attack and defence...”