Position from the game Zhongyi Tan vs Aleksandra Goryachkina, Semifinals of the World Cup 2023 Women’s Section

  • jorge@sopuli.xyzOPM
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    1 year ago

    But after Bxf4, white doesn’t have to play gxf4. Kg1, Kh1 or Ng2 stop the discovered check and allow white to capture the promoted queen.

    • putoelquelolea
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      1 year ago

      That is true. White doesn’t have to play Rxb4 after Bb4 either.

      Once white stops the discovered check with Ng2, black can either capture the rook at b7 or try for mate. White can’t move to the king to g1 or h1 because the new queen is covering that row.

      In either case, you are moving the bishop out of the way for a discovered check. My question is wouldn’t it be better to get a pawn out of it?

      • jorge@sopuli.xyzOPM
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        1 year ago

        That is true. White doesn’t have to play Rxb4 after Bb4 either.

        It doesn’t matter whether white takes the bishop or not, in any case black can promote without being taken by white’s rook, for example 1…Bb4 2. Ng2 b1=Q, and white can0t take the new queen.

        Once white stops the discovered check with Ng2, black can either capture the rook at b7 or try for mate.

        I don’t think I follow you. Do you mean after 1…Bxf4 2. Ng2? How can black capture the rook? If the pawn promotes, the rook simply takes the new queen (1…Bxf4 2. Ng2 b1=Q 3. Rxb1). And trying for mate without promoting the b2 pawn seems unnecessarily complicated to me (I mean, the position is -5 in favour of black according to the engine, so probably there is some path to mate, but it isn’t obvious)

        White can’t move to the king to g1 or h1 because the new queen is covering that row.

        White moves the king before the pawn promotes: 1…Bxf4 2. Kh1. And again, if you promote, the white rook simply takes the new queen 1…Bxf4 2. Kh1 b1=Q+ 3. Rxb1

        • putoelquelolea
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          1 year ago

          I see. You are planning on moving the king before the discovered check. That was not mentioned in the original solution, and also changes the play for:

          1. … Bb4

          If we use your solution we can’t use discovered check for the same reason, because:

          1. Kh1 b1Q+

          Also gives:

          1. Rxb1
          • jorge@sopuli.xyzOPM
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            1 year ago

            No. After 1… Bb4 2. Kh1 b1=Q#, white rook can’t take the queen because its path is blocked by the bishop in b4. In fact, it is checkmate.

            • putoelquelolea
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              1 year ago

              It looks like we are talking about two different things and will never reach a consensus

              • jorge@sopuli.xyzOPM
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                1 year ago

                This is the position after 1… Bb4:

                after 2. Kh1:

                and after 2… b1=Q#

                How are you proposing that 3. Rxb1 is going to happen?

                • putoelquelolea
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                  1 year ago

                  My question was: what would happen if black did not move his bishop to b4, but rather took the pawn at f4. So far, the answers I keep getting begin with b4

                  • jorge@sopuli.xyzOPM
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                    1 year ago

                    after 1… Bxf4

                    White can play either 2.Ng2, 2.Kh1 or 2.Kg1

                    which in all cases stop the threat of 2… b1=Q because now 3. Rxb1 is available

                    The move Bb4 has two functions: clearing the way for a possible discovered check in the second rank, and shielding the promotion square from white rook. On the other hand, the move Bxf4 only clears the way for the discovered check, but doesn’t protect b1, so promotion is no longer possible.