1. c2c4 Behind in the result and with just one last white game So needs to  play for a win at any cost. 1... g8f6  2. b1c3  2... e7e5  3. g1f3  3... b8c6  4. e2e3  4... f8b4  5. d1c2  5... e8g8  6. c3d5  6... f8e8  7. c2f5 A positionally aggressive line introduced in  the tournament practice by R. Keene and later adopted by V. Kortschnoi.  White wants to use weakening of the f7-square and double the opponent's  pawns on the kingside. 7... d7d6  8. d5f6  8... d8f6  9. f5f6 