, Muskogee, OK

January 31, 2013

Sometimes a bark is worth more than a bite

— Magnus Carlsen, who is the world’s number one ranked chess player, easily won the prestigious annual January chess tournament in Wijk ann Zee, Netherlands. In the next to last round of the tournament the U.S.’s best player Hikaru Nakamura faced Carlsen. Nakamura gambled and lost against the world’s top rated player.

This week’s position is from that game. Carlsen is white; Nakamura, black. The position is very imbalanced. Black’s king sits in the center of the board with the enemy just outside the palace. Similarly, white’s king is cornered with an enemy knight and pawn holding a knife to the white monarch’s throat.

Carlsen, however, ignored black’s knight and pawn. He opted instead to create more threats while protecting his bishop pair. With this hint in mind please try to find Carlsen’s move.

A tempting but incorrect move for white is to capture black’s h3 pawn with the bishop on f5. Black’s rook on g8 then takes white’s bishop on g5, followed by white’s bishop on h3 eliminating the knight on g2. While white is still better, white has traded its threats for black’s threats, which benefits black.

Carlsen saw that the value of his bishop pair and advanced f6 pawn combined with a new pin was crushing. He thus moved his queen to h5 (Qh5).

The white queen guards the g5 bishop while pinning black’s f7 pawn. White threatens to exploit the pin and move the f5 bishop to e6, creating a mating threat. Nakamura played the best reply, moving his knight on d7 to b6. This lets his queen guard f7.

But Carlsen moved his f5 bishop to e6 anyway. White threatens to block the black queen’s defense of f7 by moving the c6 knight to e7, which would be supported by the advanced f6 pawn.

If black tries to block the white queen’s pin by moving the g8 rook to g6, for example, white’s queen takes the rook. After black’s f7 pawn takes the queen, white’s f6 pawn marches onto f7, checking black. Black can only stop mate by taking white’s pawn with its queen, which is in turn taken by white’s f1 rook. This results in white owning an extra rook and securing an overwhelming positional edge.

Nakamura decided to capture Carlsen’s bishop on g5 with his g8 rook, which was captured by Carlsen’s queen. Nakamura’s f7 pawn now took white’s bishop on e6, which was captured by the d5 pawn.

Black has no viable defense against the f6 pawn moving to f7 and checking black. Black can only stop mate by trading its queen for white’s pawn on f7. Consequently, Nakamura resigned before Carlsen advanced his pawn to f7.

Carlsen Qh5 move showed that the pin along with its related threats were more valuable than winning black’s h3 pawn and knight on g2. Sometimes a bark is worth more than a bite.