# Situations of underpromoting the pawn

I recently came across a wonderful article on Chess.com about under promotion of pawns. One of the situations is here:

[FEN "8/8/1KP5/3r4/8/8/8/k7 w - - 0 1"]
[Date "1895.??.??"]
[White "Saavedra, Fernando"]
[Result "1-0"]
[Setup "1"]
[FEN "8/8/1KP5/3r4/8/8/8/k7 w - - 0 1"]
[Plycount "13"]
[Sourcedate "2014.05.08"]

1.c7 Rd6+ 2. Kb5 Rd5+ 3. Kb4 Rd4+ 4. Kb3 Rd3+ 5. Kc2 Rd4


In the above game using Rook instead of Queen for promotion seems to win it for white.

If white is promoted to Queen, then 6.. Rc4+ and Qxc4 is forced which will be a stalemate.

How many other situations can we consider for the under promotion?

• Take a look at the answers to these questions: chess.stackexchange.com/questions/725/… May 25, 2015 at 7:11
• Read up on the "Babson Task" -- a type of chess problem where white must force mate in x moves, and where black can defend by promoting a pawn. For each piece that pawn can promote to, the only white move that wins is a promotion to the same piece May 25, 2015 at 20:03

Here's my take on this question, since I find the other two answers lacking actual examples.

Knight promotion

In the situation below black has been trying to prevent white from promoting the pawn (white has earlier given up his rook for a black pawn). White manages to promote, but only one of the promotions secures a (tablebase) draw.

[white "Alexander Evdokimov"]
[black "Evgeni Ellinovich Sveshnikov"]
[event "56th Russian Championships, 2003"]
[fen "8/r3KP2/8/4k3/8/8/8/8 w - - 0 1"]

1.Ke8 Ke6 2. f8=N+! {2. ... Ra8+ otherwise} 1/2-1/2


Here, white underpromotes to avoid stalemate.

[white "Iroda Khamrakulova"]
[black "Ekaterina Ubiennykh"]
[event "WJun Women, 2001"]
[fen "6r1/k1P5/P7/1K1R4/8/8/8/8 w - - 0 1"]

1. Rd8 {according to tablebases, Rd7 wins faster} Rxd8 {again, there are slower ways for black to lose} 2. cxd8=N! {stalemate if rook or queen is promoted, a draw if a bishop (wrong corner)} 1-0


In the situation below, white has just played Qg3. Black underpromotes to gain a tempo, as white threatens checkmate and fork rival king and queen.

[white "Zvonimir Mestrovic"]
[black "Svetozar Gligoric"]
[event "Hastings, 1971/72"]
[fen "7k/1p2Npbp/8/2P5/1P1r4/3b2QP/3q1pPK/2RB4 b - - 0 1"]

1. f1=N+! 0-1


In the position below, white underpromotes to deliver a checkmate.

[white "William Strum"]
[black "John McManus"]
[event "Eastern Open, 1997"]
[fen "8/p3R2P/1p4k1/6p1/2rB2KR/P1r5/8/8 w - - 0 1"]

1. h8=N+ 1-0


Last, but not least, a very neat opening trap. Black undepromotes to gain a tempo and subsequently win the white queen.

[fen "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]

1. d4 d5 2. c4 e5 3. dxe5 d4 4. e3 Bb4+ 5. Bd2 dxe3 6. Bxb4 exf2+ 7. Ke2 fxg1=N+ 8. Rxg1 Bg4+ 0-1


Rook promotion

Arguably, less spectacular than knight underpromotions. One would promote to a rook in order to avoid a stalemate (otherwise, anything a rook can do, a queen also can). Two examples from endgames below.

[fen "6k1/6P1/5K2/8/8/6P1/8/8 w - - 0 1"]

1. g4 Kh7 2. Kf7 Kh6 3. g8=R! {stalemate in case of queen promotion. Knight promotion would also win, but would take longer} 1-0


.

[fen "4r3/5RPk/5K2/8/8/8/8/8 w - - 0 1"]

1. Rf8 Rxf8 2. gxf8=R {stalemate in case of queen promotion, unable to win if promoting to a minor piece} 1-0


Bishop promotion These are the rarest of the bunch. Usually would be to avoid a stalemate, or some other extraordinary situations, since otherwise, anything a bishop can do, a queen also can. First, a classic.

[fen "4Q3/Pq4pk/5p1p/5P1K/6PP/8/8/8 w - - 0 1"]

1. a8=B! {promoting to rook or queen runs into Qf7+ and stalemate} 1-0


Another endgame.

[fen "8/8/5b2/8/K7/4N3/kp6/8 w - - 0 1"]

1. Nd1 b1=B! {Nc3+ if promoting to rook or queen - draw} 0-1


Lastly, this amazing position.

[fen "1r5K/6PP/8/8/8/1k4q1/6P1/8 w - - 0 1"]

1. g8=B+! {black must move the king and it is a stalemate} Kb4 (1... Rxg8+ 2. hxg8=Q+ Qxg8+ 3. Kxg8 {and the g2 pawn will inevitably promote - white wins}) 1/2-1/2


Sources for these and many more examples

http://timkr.home.xs4all.nl/chess2/minor.htm

http://www.chessgames.com/perl/chesscollection?cid=1000028

Here are some more extreme situations to consider. The first two diagrams are merely for completeness.

[Title "Grigory Popov, 1st-5th Prize, Vladislav Tarasiuk-50 JT 2018, Mate In 33"]
[FEN "5B2/PPPPPPPP/q7/3rppp1/2p4p/3p3n/5p2/3N1Kbk w - - 0 1"]

1. a8=Q! Qa5 2. Qxa5 Rxa5 3. b8=Q Ra1 4. Qa8+ Rxa8 5. e8=Q Ra1 6. Qa8+ Rxa8 7. Ba3 Rxa3 8. g8=Q Ra1 9. Qa8+ Rxa8 10. c8=Q Ra1 11. Qc6+ e4 12. Qa4 Rxa4 13. h8=Q Rb4 14. Nc3 Rb2 15. d8=Q Re2 16. Nxe2 dxe2+ 17. Kxe2 Kg2 18. Qa1 Nf4+ 19. Kd2 f1=N+ 20. Kc3 Ne2+ 21. Kxc4 Be3 22. f8=Q Neg3 23. Qfa3 Nd2+ 24. Kb5 Bf4 25. Qd1 Ndf1 26. Qa2+ Nd2 27. Qaxd2+ Bxd2 28. Q8xd2+ Kh3 29. Qf2 e3 30. Qxe3 f4 31. Qf2 Nf1 32. Qdf3+ Ng3 33. Q2g2#

[Title "Karlheinz Bachmann, Die Schwalbe 4/1998, Mate In 9"]
[FEN "8/PPPPPP2/7K/4rP2/8/6Pp/4Nprp/5Qnk w - - 0 1"]

1. e8=R Rxf5 2. f8=R Rc5 3. c8=R Ra5 4. a8=R Rd5 5. d8=R Rb5 6. b8=R Rh5+ 7. Kxh5 Rxg3 8. Nxg3#

[Title "David Zimbeck, Die Schwalbe 2/2003, Mate In 6"]
[FEN "5bbk/PPPPPB1p/4p2N/4p1PN/1q2P1R1/R4K2/3r4/6BQ w - - 0 1"]

1. exf8=B Qxf8 2. d8=B Rxd8 3. cxd8=B Qxd8 4. b8=B Qxb8 5. axb8=B Bxf7 6. Bxe5#

[Title "Andre Cheron, Journal de Geneve 2/4/1964, Mate In 8"]
[FEN "N7/PPPPPPPP/K1k3rB/b1pnnb1p/8/1r6/pp3p2/7q w - - 0 1"]

1. b8=N+ Rxb8 2. axb8=N+ Kd6 3. c8=N+ Ke6 4. d8=N+ Bxd85. exd8=N+ Kf6 6. g8=N+ Rxg8 7. hxg8=N+ Kg6 8. f8=N#

• Thanks for the answer but those positions are practically impossible I would say.
– m4n0
Nov 19, 2019 at 9:35