Answers.Body: <p>It's ok, top players do it too. But be prepared to face the consequence when the underpromotion doesn't work out.</p>
  
  <p><a href="http://www.chessgames.com/perl/chessgame?gid=1879525" rel="noreferrer">http://www.chessgames.com/perl/chessgame?gid=1879525</a></p>
  
  <p>(Move 77... f1=N by Nakamura)</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-07-02T14:03:50.633Z
Answers.Text: Nice blunder that one.
Answers.UserDisplayName: Joshua
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-07-05T13:42:15.463Z
Answers.Text: Hah, I saw that one live. Incredible.
Answers.UserDisplayName: BlindKungFuMaster
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2022-07-28T07:36:37.613Z
Answers.Text: Even worse! A bishop would have done it too, f1N is technically no blunder, run the game through a tablebase and repeatedly hit your head against the wall...Admittedly blitz, but super GMs should know their rook endgames by heart!
Answers.UserDisplayName: Hauke Reddmann
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-07-02T13:13:06.320Z
Answers.LastActivityDate: 2018-07-02T13:13:06.320Z
Answers.UserDisplayName: jf328
Answers.Body: <p>Underpromotion might be &quot;unsportsmanlike&quot; if you do it toy with your opponent
  (e.g. promoting several pawns to Bishops for the heck of it),
  but if you do it to make the win easier then there's absolutely nothing
  wrong with it, even if it's because you're more comfortable winning with
  KR/K than KQ/K (which must be very unusual, but is not
  a failure of sportsmanship).</p>
  <p>Tim Krabbé has a nice collection of examples of promotion to R or B
  in actual play: <a href="https://timkr.home.xs4all.nl/chess2/minor.htm" rel="noreferrer">https://timkr.home.xs4all.nl/chess2/minor.htm</a> .
  In a few cases the underpromotion is the only winning move,
  or at least the only winning promotion (because Q would stalemate
  and N is not strong enough).  But there are also cases where
  a Queen would win too but with more difficulty because you must
  deal with a stalemate defense -- close to what you describe
  albeit at a higher level of play.  See the four examples introduced by</p>
  <blockquote>
  <p>in all of the following examples promotion to Queen would also have worked.
  But sometimes it would have been tricky, and in most cases the Rook promotion
  was the most sensible and practical thing to do:
  why think if you don't have to.</p>
  </blockquote>
  
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Answers.CreationDate: 2022-07-28T15:10:59.510Z
Answers.LastActivityDate: 2022-07-28T15:10:59.510Z
Answers.UserDisplayName: Noam D. Elkies
Answers.Body: <p>You may choose any legal move you like; your opponent's sole recourse is to prove that it wasn't good enough.</p>
  <p>This also applies to fighting on in lost games. There is always the possibility that the opponent will blunder away their advantage, or even the game itself.</p>
  <p>I applied this principle when faced with an opponent with a bare king who refused to resign. I promoted my two pawns to knights for a total of three, and delivered a novel checkmate with K+3N. (The theory is known, apparently but I couldn't find any other examples so I developed my own).</p>
  <p>It was a lot more challenging than just ginning up a simple Q+R mate, and even drew a small audience.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2022-07-27T18:41:28.103Z
Answers.LastActivityDate: 2022-07-27T18:41:28.103Z
Answers.UserDisplayName: jaxter
Answers.Body: <p>Here's a game with pawn promotion to a Knight for checkmate.  Nothing unsportsmanlike when one plays to win as far as I am concerned.</p>
  
  <p>Zvonimir Mestrovic vs Svetozar Gligoric</p>
  
  <p><a href="https://lichess.org/RiMAvMwD" rel="nofollow noreferrer">https://lichess.org/RiMAvMwD</a></p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-07-04T21:30:24.940Z
Answers.LastActivityDate: 2018-07-04T21:30:24.940Z
Answers.UserDisplayName: hangejj
Answers.Body: <p>If, as you say, you are "improving your chances", then it's not unsportsmanlike.  Even if your opponent misunderstands, he doesn't really have much to complain about - if he doesn't want to play on he is free to resign.</p>
  
  <blockquote>
    <p>I barely care about my opponent not resigning when he should.</p>
  </blockquote>
  
  <p>Good, because demanding that your opponent resign IS unsportsmanlike.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2018-07-01T20:37:53.573Z
Answers.LastActivityDate: 2018-07-01T20:37:53.573Z
Answers.UserDisplayName: D M
Body: <p>Is it unsportsmanlike to underpromote a pawn to improve my chances? Sometimes I reach a won endgame where underpromoting my pawn will result in a slower but easier final checkmate.</p>
  
  <p>Old example, easiest to understand: I was far better practiced at K-R vs K than K-Q vs K so I promoted a lone pawn to a rook. Improvising K-Q vs K would have had too high of stalemate chance for my taste.</p>
  
  <p>Recent example: I deliberately underpromoted a pawn to a rook rather than a queen while having a queen. This makes mate in 9 moves worst case rather than 8 and again reduces the accidental stalemate odds dramatically.</p>
  
  <p>I barely care about my opponent not resigning when he should. Primary reason: I once played out a losing game, sacrificing my last piece to push the ending int B-N endgame. My opponent said I should resign as he had a book endgame. I said, "Yes, but I don't think you can do it." Fifty move rule got him: B-N is tight and he was out of practice.</p>
  
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2018-07-01T20:35:17.557Z
Comments.Text: No, it is not unsportsmanlike.
Comments.UserDisplayName: Cleveland
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2018-07-02T10:19:32.183Z
Comments.Text: "I barely care about my opponent not resigning when he should" -- if you really don't care you would not mention it at all. Now you sound like a TV drama character, "I don't care you don't love me anymore!" (tear droppin' =)
Comments.UserDisplayName: lenik
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2018-07-02T14:05:48.243Z
Comments.Text: @lenik: Some people would call failure to resign a lost cause unsportsmanlike and I wanted to discourage answers depending on it.
Comments.UserDisplayName: Joshua
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2018-07-12T22:21:30.017Z
Comments.Text: hahaha love the ending. But in the time you came here to write this you could easily have learned the KQ vs K ending. You shouldn't be too afraid of stalemates, and put your time on learning properly the basic endings. That will save you a lot of points since you will be able to mate faster, avoiding losses/draws on time, and with practice it should be fairly easy to avoid stalemates. For example, in KQ vs K you can always mate in 10 or less moves, in KR vs K you can always mate in 17 or less moves. That could be the difference between winning and losing.
Comments.UserDisplayName: Ivan Lerner
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2018-07-12T23:29:11.810Z
Comments.Text: @IvanLerner: I said old example. It does not represent my current skill level.
Comments.UserDisplayName: Joshua
Tags: <pawn-promotion><sportsmanship>
Title: Is it unsportsmanlike to underpromote to improve my chances?
ThreadText: # Is it unsportsmanlike to underpromote to improve my chances?
  
  (Asked by: username_0 on 2018-07-01)
  
  Is it unsportsmanlike to underpromote a pawn to improve my chances? Sometimes I reach a won endgame where underpromoting my pawn will result in a slower but easier final checkmate.
  
  Old example, easiest to understand: I was far better practiced at K-R vs K than K-Q vs K so I promoted a lone pawn to a rook. Improvising K-Q vs K would have had too high of stalemate chance for my taste.
  
  Recent example: I deliberately underpromoted a pawn to a rook rather than a queen while having a queen. This makes mate in 9 moves worst case rather than 8 and again reduces the accidental stalemate odds dramatically.
  
  I barely care about my opponent not resigning when he should. Primary reason: I once played out a losing game, sacrificing my last piece to push the ending int B-N endgame. My opponent said I should resign as he had a book endgame. I said, "Yes, but I don't think you can do it." Fifty move rule got him: B-N is tight and he was out of practice.
  
  **Tags:** pawn-promotion, sportsmanship
  
  > **Comments:**
  > **username_1**: No, it is not unsportsmanlike.  
  > **username_2**: "I barely care about my opponent not resigning when he should" -- if you really don't care you would not mention it at all. Now you sound like a TV drama character, "I don't care you don't love me anymore!" (tear droppin' =)  
  > **username_0**: @username_2: Some people would call failure to resign a lost cause unsportsmanlike and I wanted to discourage answers depending on it.  
  > **username_3**: hahaha love the ending. But in the time you came here to write this you could easily have learned the KQ vs K ending. You shouldn't be too afraid of stalemates, and put your time on learning properly the basic endings. That will save you a lot of points since you will be able to mate faster, avoiding losses/draws on time, and with practice it should be fairly easy to avoid stalemates. For example, in KQ vs K you can always mate in 10 or less moves, in KR vs K you can always mate in 17 or less moves. That could be the difference between winning and losing.  
  > **username_0**: @IvanLerner: I said old example. It does not represent my current skill level.  
  
  ---
  
  ## 5 answers
  
  ### Answer by username_10 on 2018-07-01. Score: 20 | Accepted answer
  
  If, as you say, you are "improving your chances", then it's not unsportsmanlike. Even if your opponent misunderstands, he doesn't really have much to complain about - if he doesn't want to play on he is free to resign.
  
  > I barely care about my opponent not resigning when he should.
  
  Good, because demanding that your opponent resign IS unsportsmanlike.
  
  
  ---
  
  ### Answer by username_4 on 2018-07-02. Score: 8
  
  It's ok, top players do it too. But be prepared to face the consequence when the underpromotion doesn't work out.
  
  <http://www.chessgames.com/perl/chessgame?gid=1879525>
  
  (Move 77... f1=N by Nakamura)
  
  > **Comments:**
  > **username_0**: Nice blunder that one.  
  > **username_5**: Hah, I saw that one live. Incredible.  
  > **username_6**: Even worse! A bishop would have done it too, f1N is technically no blunder, run the game through a tablebase and repeatedly hit your head against the wall...Admittedly blitz, but super GMs should know their rook endgames by heart!  
  
  ---
  
  ### Answer by username_7 on 2022-07-28. Score: 6
  
  Underpromotion might be "unsportsmanlike" if you do it toy with your opponent
  (e.g. promoting several pawns to Bishops for the heck of it),
  but if you do it to make the win easier then there's absolutely nothing
  wrong with it, even if it's because you're more comfortable winning with
  KR/K than KQ/K (which must be very unusual, but is not
  a failure of sportsmanship).
  
  Tim Krabbé has a nice collection of examples of promotion to R or B
  in actual play: <https://timkr.home.xs4all.nl/chess2/minor.htm> .
  In a few cases the underpromotion is the only winning move,
  or at least the only winning promotion (because Q would stalemate
  and N is not strong enough). But there are also cases where
  a Queen would win too but with more difficulty because you must
  deal with a stalemate defense -- close to what you describe
  albeit at a higher level of play. See the four examples introduced by
  
  > in all of the following examples promotion to Queen would also have worked.
  > But sometimes it would have been tricky, and in most cases the Rook promotion
  > was the most sensible and practical thing to do:
  > why think if you don't have to.
  
  
  ---
  
  ### Answer by username_8 on 2022-07-27. Score: 5
  
  You may choose any legal move you like; your opponent's sole recourse is to prove that it wasn't good enough.
  
  This also applies to fighting on in lost games. There is always the possibility that the opponent will blunder away their advantage, or even the game itself.
  
  I applied this principle when faced with an opponent with a bare king who refused to resign. I promoted my two pawns to knights for a total of three, and delivered a novel checkmate with K+3N. (The theory is known, apparently but I couldn't find any other examples so I developed my own).
  
  It was a lot more challenging than just ginning up a simple Q+R mate, and even drew a small audience.
  
  
  ---
  
  ### Answer by username_9 on 2018-07-04. Score: 2
  
  Here's a game with pawn promotion to a Knight for checkmate. Nothing unsportsmanlike when one plays to win as far as I am concerned.
  
  Zvonimir Mestrovic vs Svetozar Gligoric
  
  <https://lichess.org/RiMAvMwD>
  
  
  ---
  
  