Under promotions for pawns during a match game

[Simon Brown]

I saw Jack's mate in 4 immediately. Was trying to create a mate in 3 but Nd4 fails.

Does it start with Kb5?

No.

What Loz said.

All those things fail to Bb8 or Bc7, as did my attempt to mate in 3. Remember it's not a problem

[Christopher Kreuzer]

All those things fail to Bb8 or Bc7, as did my attempt to mate in 3. Remember it's not a problem

I can see it is not a problem. There are trivial ways to win. In some ways that does make it more like a problem. I can see that Black can mess things up by taking the pawns (or threatening to take them). It does involve an underpromotion, but that just leaves me even more befuddled...

[Christopher Kreuzer]

Oh, OK, I've seen it now...

(It was the first move I looked at and then rejected and never went back to it!)

[Michael Farthing]

This is one of the best topics going at the moment! Thanks to those who have posted these interesting positions. Please sir, can I have some more?

[LawrenceCooper]

All those things fail to Bb8 or Bc7, as did my attempt to mate in 3. Remember it's not a problem

I can see it is not a problem. There are trivial ways to win. In some ways that does make it more like a problem. I can see that Black can mess things up by taking the pawns (or threatening to take them). It does involve an underpromotion, but that just leaves me even more befuddled...

The solution is probably the first line you looked at but without finding the key third move.

[Kevin O'Rourke]

can anyone else remember a position in a game where the pawn is hanging on the 7th and the thought of making it a Knight cropped into your head?

Sometimes when pieces are swarming near by it might carry a threat of a fork if the King and Queen get too close or King and rook.

[Roger de Coverly]

Please sir, can I have some more?

Searching a database for positions with three Knights is one way of finding them.

This is an amusing one from a Women's tournament in Georgia. White spotted the mate in 1, but it's mate in 2 for Black on promotion to a Queen.

[FEN "8/6P1/5k1N/1p1KnN2/p1r5/3n4/8/6R1 w - - 1 53"]

[Ian Thompson]

This is one of the best topics going at the moment! Thanks to those who have posted these interesting positions. Please sir, can I have some more?

Here's a PGN file of games ending with a knight promotion giving mate -

knight_mates.pgn

Searching for promotions to a knight somewhere in the game returned almost 2000 games.

[Matt Fletcher]

I haven't solved Matt's poser either (does it start with Qh6+?).

Very nice puzzle! It does start with Qh6+, and I was stuck for a while on how to meet the Rg6 defence, but have got it now (EDIT: though some of the lines end in draws? Is it a win for White or a draw?).

It does start with Qh6+, and it is a win - not sure where your drawing line comes from?

After 1...Rg6 you play 2.d8=Q+! Qxd8 3. Qh4+ which I guess you found.

The Knight promotion line is 1.Qh6+ Kf7 2.Qxh7+ Rg7 3.d8=N+! Qxd8 (moving the King gets you in all sorts of trouble) 4.Qxf5+ followed by Qxc5 which should be winning without too much trouble. The underpromotion is the only way to get to a winning position in this line.

So the only other sensible line (which happened in the game) is 2.Qxh7+ Kf6 - White to play and win from here:

6r1/3P3Q/5k2/1pbq1p2/5P2/8/6PP/4R2K w - - 0 3

[Christopher Kreuzer]

So the only other sensible line (which happened in the game) is 2.Qxh7+ Kf6 - White to play and win from here:

6r1/3P3Q/5k2/1pbq1p2/5P2/8/6PP/4R2K w - - 0 3

Thank-you. I found the other lines. I thought this was a drawing line, but now you have put it up on the screen, I can see what the winning line is. Difficult (for me) to see from that far off. How many moves back did you analyse that and did you see it all in the game? Did Black blunder in allowing you to play this line, or were you always better leading up to this finish?

[Matt Fletcher]

How many moves back did you analyse that and did you see it all in the game? Did Black blunder in allowing you to play this line, or were you always better leading up to this finish?

Sad to say, it was an adjournment, though it was a few moves on from the adjourned position. Black did blunder with Rg8 and it was a tactic I'd analysed before the re-start...

Anyway, here's a nice Shirov game - also featuring a Black testudo

[Event "Tilburg Fontys"] [Site "Tilburg"] [Date "1996.??.??"] [Round "2"] [White "Shirov, Alexei"] [Black "Almasi, Zoltan"] [Result "1-0"] [ECO "C67"] [WhiteElo "2685"] [BlackElo "2650"] [PlyCount "71"] [EventDate "1996.10.11"] [EventType "tourn"] [EventRounds "11"] [EventCountry "NED"] [EventCategory "16"] [Source "ChessBase"] [SourceDate "1997.02.01"] 1. e4 e5 2. Nf3 Nc6 3. Bb5 Nf6 4. O-O Nxe4 5. d4 Nd6 6. Bxc6 dxc6 7. dxe5 Nf5 8. Qxd8+ Kxd8 9. Nc3 Ne7 10. Nd4 Ng6 11. f4 Bc5 12. Be3 Bb6 13. Rae1 Nh4 14. e6 fxe6 15. Nxe6+ Bxe6 16. Bxb6 axb6 17. Rxe6 Kd7 18. Rfe1 Rae8 19. Rxe8 Rxe8 20. Rxe8 Kxe8 21. Kf2 Nf5 22. Ne4 c5 23. g4 Nh6 24. Kf3 Nf7 25. h4 Ke7 26. Ng5 Nd6 27. Nxh7 Nc4 28. f5 Nxb2 29. g5 Nc4 30. h5 b5 31. Kf4 Na3 32. h6 gxh6 33. g6 Nc4 34. f6+ Ke6 35. f7 Ne5 36. f8=N+ 1-0

[Jesper Norgaard]

This is one of the best topics going at the moment! Thanks to those who have posted these interesting positions. Please sir, can I have some more?

Although the title of this thread indicates OTB play, I want to divert a little to one of the most diverse studies ever composed because White needs to underpromote to knight, bishop and rook to be able to draw. In fact a new study has been proposed by Jan Rusinek which obligates taking a queen too in the first part of the study, to obtain the draw in the same way as the original study.

See https://en.wikipedia.org/wiki/Jan_Rusinek

The key moves are 3.g8=N+! and 5.a8=B!! and 8.b8=R!! with White playing for stalemate

Of course the stalemate is also the point in this position:

8/8/8/8/8/4K3/2R3pp/2R4k

It is obvious why 1...g1=Q+ 2.Kf3 is suicidal, the queen has only grief from the extra moves on the first rank. Instead 1...g1=B+ 2.Kf3 stalemate draws.

[Kevin O'Rourke]

This is one of the best topics going at the moment! Thanks to those who have posted these interesting positions. Please sir, can I have some more?

Although the title of this thread indicates OTB play, I want to divert a little to one of the most diverse studies ever composed because White needs to underpromote to knight, bishop and rook to be able to draw. In fact a new study has been proposed by Jan Rusinek which obligates taking a queen too in the first part of the study, to obtain the draw in the same way as the original study.

See https://en.wikipedia.org/wiki/Jan_Rusinek

The key moves are 3.g8=N+! and 5.a8=B!! and 8.b8=R!! with White playing for stalemate

Of course the stalemate is also the point in this position:

8/8/8/8/8/4K3/2R3pp/2R4k

It is obvious why 1...g1=Q+ 2.Kf3 is suicidal, the queen has only grief from the extra moves on the first rank. Instead 1...g1=B+ 2.Kf3 stalemate draws.

very clever

[IM Jack Rudd]

Of course, in a real game, you'd try 2.Ke2 and see whether you could get anywhere.

[Jon Mahony]

I was the victim of this in a congress game last year - I’d turned down several draw offers, and eventually got into a position where I had 2 strong passed pawns but my opponent had an isolated PP ready to queen. I had calculated a very simple combo where if my opponent queened I won his existing queen and then won with my pawns.

To my horror my opponent pushed his pawn and said “Knight, check!” something I’d stupidly not even considered (first time it’d ever happened to me in a game outside the internet, and that’s rare) I had to move my King and my opponent then had 3 Knights on the board (brain bending) I think he eventually sacrificed one for both my strong pawns or mated me, I can’t remember - either way, not nice. I’ll have to dig out the game on my database. I always look out for it now!