Junior 8 confirms patzer move

[Guest]

Archived from groups: rec.games.chess.computer (More info?)

After making a blunder in a drawn position, I loaded up Junior to see where
I went wrong. Imagine my surprise when Junior 8 suggested the same blunder
as I made!!

[Event "Game 674452"]
[Site www.brainking.com]
[Date "2005.02.27"]
[Round "?"]
[White "MacNair, Adrian"]
[Black "Corporation (11-0-6)"]
[Result "0-1"]
[ECO "C40"]
[BlackElo "1779"]
[PlyCount "77"]

1. e4 e5 2. Nf3 d6 3. d4 exd4 4. Nxd4 Nf6 5. Nc3 a6 6. Be2 Be7 7. O-O O-O 8.
f4 c5 9. Nb3 b5 10. e5 dxe5 11. Qxd8 (11. fxe5 Nfd7 (11... Qxd1 12. Rxd1
Ng4) 12. Bf3) 11... Rxd8 12. fxe5 Ne8 13. Bf3 Ra7 14. Be3 Rc7 15. Bf4 (15.
Nd5 Rcd7 16. Rad1 Nc6 17. Na5 Nxa5 18. Nxe7+ Kh8 19. Nxc8) 15... Be6 16.
Rad1 Bxb3 17. Rxd8 Bxd8 18. Rd1 Rd7 19. Rxd7 Nxd7 20. cxb3 Nf8 21. Ne4 Ne6
22. Bg3 Be7 23. Bf2 f6 24. exf6 Nxf6 25. Nxf6+ Bxf6 26. Bd5 Kf7 27. Bxe6+
Kxe6 28. Bxc5 Bxb2 {The game has reached a drawn position} 29. Kf2 Kd5 30.
Be7 Ke4 31. Ke2 h5 32. a4 bxa4 33. bxa4 Be5 34. g3 Bc7 35. Bf8 g5 36. Be7 g4
37. Bf6 Bb6 38. Bg5 Kd5 39. Be3?? 0-1

Junior 8 suggests the move 39.Be3 for a whopping 1:08 before changing to
Bf4. To a normal player, anyone can see that 39.Be3?? is immediately losing
due to the proximity of the black king:

39...Bxe3 40.Kxe3 Kc4 {winning}

Junior 8 Analysis:
39. Be3 (-0.29) 0:00:04
(-0.63) 0:00:32
(-1.60) 0:01:01
Bf4 (-1.25) 0:01:08
Kd3 (-1.20) 0:01:19

Here are some other chess programs:

Gandalf 5
39. Kd3 (-1.31) 0:00:09
Same eval at 1:19

CM9000
39. Kd3 (-1.05) 0:00:01
(-0.36) 0:00:09
(-1.28) 0:00:17
(-1.41) 0:00:38
Same eval at 1:19

ProDeo 1.1
39. Be3 (-0.17) 0:00:05
(-2.84) 0:00:10
Kd3 (-0.14) 0:00:17
(-0.80) 0:00:24
(-0.99) 0:00:57
Same eval at 1:19

 

[Guest]

Archived from groups: rec.games.chess.computer (More info?)

Adrian MacNair wrote:
> After making a blunder in a drawn position, I loaded up Junior to see where
> I went wrong. Imagine my surprise when Junior 8 suggested the same blunder
> as I made!!

The "blunder" was made in an already lost position. It just made things
easier but didn't change the outcome. The real error lies somewhere before.

> 27. Bxe6+

I think this is definitely a weak move. After this move White fights for
the draw. 27. Bxc5 would have been fine. I don't know if the bishops
pair is enough to win it for White, but it should be a comfortable draw
at least.

> Kxe6 28. Bxc5 Bxb2 {The game has reached a drawn position} 29. Kf2 Kd5 30.
> Be7 Ke4 31. Ke2 h5 32. a4

Inaccurate, could be the decisive error. It weakens the queenside so
that Black's king can attack it. Better is 33. Bc5 which denies Black
the way to the queenside. The pawn on b3 guards c4.

> bxa4 33. bxa4 Be5

More forcing is 33...Kd4 34. Kd2 Kc4 35. Kc2 Be5 36. h3 Bd4 and Black is
winning. See next move.

34. g3

After 35. h3 Kd4 36. Kd2 Kc4 37. Kc2 Bd4 38. Bd6 g6 with the plan Bc5
and Kb4 Black looks winning. The pawn endgame after 38. Be7 or 38. g3
Bc5 39. Bxc5 Kxc5 is won for Black. If 38. g4 hxg4 39. hxg4 Bf6 Black
plans to march to the kingside and attack g4. 40. Bc7 (keeps f4 under
control. On 40. Bf8 Kd4 wins) 40...Be7 (not 40...Kb4 41. a5 draw)
Zugzwang 41. Ba5 (if the bishop sticks to the b8-h2 diagonal Kb4 wins)
41...Kd4 and wins.

> Bc7 35. Bf8

A little better is 35. Kf2 where the bishop keeps control of g5. 35. Kf2
Bb6+ 36. Ke2 Kd4 37. Kf3 Ke5 (37...Kc4 38. Kf4 =) 38. g4 looks like a
draw. Black has to play 35...Kf5 36. Kf3 g5 with a somewhat better king
position for White than in the game, but Black still has the upper hand.

> g5 36. Be7

Another tempo for Black who would play g4 anyway. The bishop would be
best on the a7-g1 diagonal where it is protecting the vulnerable white
kingside pawns. But as the pawn endgame is lost for White, Black can
drive the White bishop away.

> g4 37. Bf6

Keeps the black king from wandering to the queenside for a short time.

> Bb6 38. Bg5 Kd5 39. Be3?? 0-1
>
> Junior 8 suggests the move 39.Be3 for a whopping 1:08 before changing to
> Bf4. To a normal player, anyone can see that 39.Be3?? is immediately losing
> due to the proximity of the black king:
>
> 39...Bxe3 40.Kxe3 Kc4 {winning}

Well, the pawn endgame is won for Black. But so is the bishop endgame
because White can't stop the black king from attacking the queenside.

After 39. Kd3 Bg1 40. Ke2 (letting Black capture h2 is of course also
losing: 40. Bh4 (40. Bg5 Bxh2 41. Bf4 h4 -+) Bxh2 41. Ke3 Bg1+ 42. Kf4
(42. Kd3 Bd4 43. Bd8 Be5 44. Bh4 Ke6 45. Ke4 Bf6 -+) 42...Bd4 43. Kg5
(43. Bd8 Be5+ 44. Kg5 Ke4 is the same) 43...Ke4 44. Kxh5 Kf3 -+)
40...Kc4 41. Bd8 Kb4 42. a5 Kb5 43. Kd3 (43. Bc7 Bxh2 44. Kf2 h4 -+; 43.
Ke1 Bc5 and Bb4 -+) 43...Bxh2 44. Bh4 Kxa5 45. Ke4 Kb4 46. Kf5 a5 47.
Kg6 a4 48. Kxh5 Bg1! 49. Bf6 a3 50. Kxg4 Kc4 Black wins.

Claus-Juergen