White to move. Is this a win or draw?
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White to move. Is this a win or draw?
h4
Win for White
1. Qd8 Qf4+
2. Kg1 Qe3+ (or Qc1+)
3. Kf1 Qc1+ (or Qd3+)
4. Kf1 Qd2+
5. Kg3 Qe1+
6. Kf4 and King escapes.
Anon 10:27, I was thinking along the same lines you were, BUT what if 3…f4 instead of Qc1+?
Anon 10:59, after 3…f4 follows Qg5+ and c8Q mate.
First of all, the obvious move, posted by anon_8:19, is 1 h4!! It’s the ‘obvious’ move, as it gives the white king the h3 escape square from perpetual checks. I’ve tried to refute it, but I don’t see a way for black to draw. 1 h4!! is a winner.
That said, anon_10:27 comes up with another line that seems to win. The line posted does. Yet he misses a crucial drawing line by black:
“Win for White
1. Qd8 Qf4+
2. Kg1 Qe3+ (or Qc1+)”
Yes, Qe3+ 3 Kf1 etc. wins for white, and the king escapes. But exploring the alternative “(or Qc1+)” yields a draw:
1 Qd8? Qf4+
2 Kg1 Qc1+!
3 Kf2 f4!! cutting off the King!
(Note that anders j. munch points out correctly that …f4 fails miserably in the 2…Qe3+ line, as after 3 Kf1 f4 4 Qg5+! K-any 5 c8=Q++. However, in the 2…Qc1+ line, 3…f4!! wins.)
If 4 c8=Q, black has endless perpetual checks with Qd1+, etc. as the f-pawn cuts off both vital escape squares e3 and g3, so the extra queen is useless.
White’s only try here would thus be:
4 Qg5+ Kf8
5 Qxf4 QxQ
6 c8=Q+ Ke7 (or Kg7) and the game is a dead draw.
So 1 h4!! seems to be the only clear win here.
P.S. The Qe3+ line is actually a draw as well:
1 Qd8 Qf4+
2 Kg1 Qe3+
3 Kf1 Qc1+
4 Kf2 f4!! (not Qd2+??) — this transposes into the 2…Qc1+ line followed by …f4!! Black just has to make sure the queen is on c1 before playing …f4 in this variation. Key points: (1) the king is cut off by the f-pawn, and (2) the queen on c1 protects the queening square and prevents promoting with mate after Qg5+. So all the lines work for black after 1 Qd8? Again, 1 h4!! is white’s only winning move.
TVTom said…
4 Qg5+ Kf8
5 Qxf4 QxQ
6 c8=Q+ Ke7 (or Kg7) and the game is a dead draw.
How about 5. Qe5?
Anon_12:19 said…
“TVTom said…
‘4 Qg5+ Kf8
5 Qxf4 QxQ
6 c8=Q+ Ke7 (or Kg7) and the game is a dead draw.’
How about 5. Qe5?”
Well, first, none of these variations is as decisive as 1 h4!, even if white can somehow pull off a win here. You may be right about 5 Qe5, however, which is a move I didn’t consider. For example:
1 Qd8? Qf4+
2 Kg1 Qc1+!
3 Kf2 f4!
4 Qg5+ Kf8
5 Qe5 Qd2+ (or Qc2+)
6 Kg1 (if Qe2 Qxd4+ and …Qc3 and black has snatched a pawn and is doing well)
6 (Kg1) Qc1+
7 Kh2 Ke7
8 d5!! looks pretty devastating for white, as the follow-up d6!! will give white a monstrous protected passed pawn which can’t be picked off. Yeah, I think you’re right, that white can pull off the win in this variation.
Maybe a different black move in there somewhere can save the draw, but I don’t see anything better than 7…Ke7 which allows 8 d5! withe the devastating pin. Somebody with a monster chess engine can figure out if white can pull out the win with perfect play if white missed the elegant 1 h4 that wins outright to begin with.
Hmm, I posted too hastily, as going back over that Qe5 variation, maybe black can move the king immediately:
1 (Qd8?) (Qf4+)
2 (Kg1) (Qc1+!)
3 (Kf2) (f4!)
4 (Qg5+) (Kf8)
5 Qe5 Ke7!
6 d5 Qc5 stopping the fatal d6 push!
How’s that?
totally agreeing with tvtom.
1. h4 Qf4+
2. Kh3 Qc1
3. Qd8 Qh1+
4. Kg3 Qe1+
5. Kh2 and the c-pawn queens.
trips what about:
5… Qh4 check
and there is a perpetual right there.
To: anon at 2:43,
The queen is at d8 🙂