Chess School Quiz Challenge #13

Challenge

Two pawns down doesn't look good for White at first glance. But in fact White is winning. What did Sarah Papp play?

Solution

Sarah Papp is two pawns down, but has an ace up her sleeve: the passed pawn on d5. Three more steps and the passed pawn will become a queen. The closer a passed pawn is to its queening square, the stronger it is. Chess lore has derived the rule of thumb “passed pawns must march” from this principle.

The great Yasser Seirawan has reformulated this guiding principle for a 21st-century audience: “Push ‘em, baby!” the former World Championship candidate from the United States shouts when he drives his passed pawns forward in blitz chess. “Push ’em, baby!” is probably the only chess rule of thumb that has even been turned into a song. 

After this preamble, it should be clear what this is about: the passed pawn has to move, and as quickly as possible, so that Black cannot bring in forces to stop it. If White were to capture a pawn with 1.Ra7xa6?, for example, that would be greedy and a waste of time. After 1…Kg8-f7, the black king would be ready to help against the white passed pawn, and Black would have nothing to fear. 

Sarah Papp, on the other hand, immediately moved her passed pawn. 1.d5-d6! That's the only way! Now the black king would be too late: 1...Kg8-f7 2.Be7-h4+ (discovered check!), and either White wins crucial material or the passed pawn runs through. 

“Not that difficult,” you might think now – and wonder why this task is marked as difficult. This has to do with the fact that the best black defense is not easy to overcome: 1.d5-d6! Bg7-f8 2.Ra7-a8 Kg8-g7. And now?

Black has unpinned herself on the eighth rank, and it looks as if the white pawn will not advance. 3.d6-d7? Bf8xe7, and Black wins. 

But White has a tactic, the only move that wins the game: 3.Ra8-c8! Now 4.Be7xf8+ threatens, followed by 5.d6-d7, and the passed pawn advances. Black has no defense against this. 

If you saw that coming, then well done!