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Basil
19-05-2009, 10:38 PM
Black has just played 19... gxh5 (from a Tromp).

Consider the position (white to move).
1. What would you play for white's 20th?
2. Which side is better practically?
3. Which side does an engine prefer (if different)?

5rk1/pp1b2bp/3p4/q1pP3p/2P1Pp2/2NB1P2/PPQ2P2/R4K2 w - - 0 19

ER
20-05-2009, 09:38 AM
IMHO, first things first, White cannot afford to allow the bloackade on e5, therefore 20.e5 is as good as any! At some stage (sooner rather than later) White must play Ne4, then the plan is to get the King out of the way, move the R at g1 and the attack plays itself!
White is better!
I dont know about engine evaluation I don't have one!

Igor_Goldenberg
20-05-2009, 10:25 AM
If I was white and my opponent is rated lower then me, I would offer a draw :) :)
On a serious note, this is a sort of position I like to play on the black side. Objectively speaking blacks advantage is not that great, but play is simpler and much more pleasurable.

Now to the specifics.
20.e5 looks interesting.
20.e5 Bxe5 21.Qg6 looks deadly but is refuted by 21...Bf5 (22.Qh6 Bg7)
21.Ke2 can be met by 21...Qd8 or 21...Re8

Passive defence by 21.Ke2 is not sufficient, can be met by either 21...h4 (22.Rh1 h3) or 21...Be5 (which is, IMHO, is safer. 22.Rh1 Be8).

In summary, I don't envy white.

Basil
20-05-2009, 10:32 AM
20.e5 Bxe5 21.Qg6 looks deadly ...
Isn't there a d3 bishop in the way?

Igor_Goldenberg
20-05-2009, 12:21 PM
Isn't there a d3 bishop in the way?
Sorry, I meant to type 20.e5 Bxe5 21.Bxh7+ Kh8 22.Qg6

Vlad
20-05-2009, 12:38 PM
As a Tromp player myself I will go crazy with

20.e5 Bxe5 21.Bxh7+ Kh8 22.Ne4... thretening 23. Ng5... and 24. Bg8...

Capablanca-Fan
20-05-2009, 01:00 PM
If Black had played 19... Be5 instead, then I would really hate to be White; that Pe4 is in the way, as others have noted. That long diagonal is very strong for Black; he has the B-pair and a better P structure. The doubled f-pawns make it hard for White to bring pieces to attack the K-side. Meanwhile Black can aim for ... b5, or swapping Qs then ...Bxc3 and marching the K to e5, then playing on the K-side.

Basil
20-05-2009, 01:02 PM
If Black had played 19... Be5 instead...
But the questions posed in post #1, Jerry! - the questions!

Kevin Bonham
20-05-2009, 01:06 PM
Position summary: white's position is clearly not great. Black has a bishop pair and white has a lot of hemmed in pieces. Neither king is safe and also a worry for white is that the passed front black h-pawn may become a nuisance.


1. What would you play for white's 20th?

Under tournament conditions without the luxury of spending 20 minutes on one move I probably would play 20.e5, but I think the correct move is 20.Ke2.

White has a couple of options. The first is e5 immediately as discussed by the other posters. This is very tempting and I would probably play it quickly if I was short on time and playing for a win. As Igor notes, 20.e5 Bxe5 21.Bxh7+ Kh8 22.Qg6 is refuted by ...Bf5. But white can try 22.Ke2. Here black has numerous options. Igor mentions ...Qd8 and ...Re8. Another might be ...Bxc3 with ...h4 and ...Qd8 to follow. Black looks better in all these lines.

I assume Igor means 20.Ke2 when he writes:


Passive defence by 21.Ke2 is not sufficient, can be met by either 21...h4 (22.Rh1 h3) or 21...Be5 (which is, IMHO, is safer. 22.Rh1 Be8).

But there is a big difference between 20.Ke2 h4 21.e5 and 20.e5. It is that after 20.Ke2 h4 21.e5 Bxe5 22.Bxh7 Kh8 23.Qg6 Bf5 24.Qh6 Bg7 25.Qxh4 Bxh7 26.Rh1 white wins. This was too slow in the same kind of line after 20.e5 because there is no time for Rh1 as the king is in the way; 20...h4 wasted a tempo. So black has to play 22...Kf7 which may be OK but looks less safe, or else 20...Be5.

The position after 20...Be5 might not be too bad for white. It is very fiddly and strategic, but at least both black bishops are tied down defending and the h-pawn is restrained. [EDIT: remove incorrect "x" from move.]


2. Which side is better practically?

Depends on the level of player. At lower club level probably white because of the likelihood of inaccurate defence. At 1800+ level this is not very likely. Once the position blocks up a bit I would actually like to be white because I have the only knight on the board.


3. Which side does an engine prefer (if different)?

F11 prefers black, initially by about .6 but fading to a smidgin after it smells the coffee.

Ian Rout
20-05-2009, 02:22 PM
I don't like White either. My options would be e5 or somehow trying to force b4 (e.g. with a3 and Rb1), but the positions resulting from the second approach don't seem encouraging so I'd probably decide a desperate e5 is justified.

Igor_Goldenberg
20-05-2009, 02:25 PM
White has a couple of options. The first is e5 immediately as discussed by the other posters. This is very tempting and I would probably play it quickly if I was short on time and playing for a win. As Igor notes, 20.e5 Bxe5 21.Bxh7+ Kh8 22.Qg6 is refuted by ...Bf5. But white can try 22.Ke2. Here black has numerous options. Igor mentions ...Qd8 and ...Re8. Another might be ...Bxc3 with ...h4 and ...Qd8 to follow. Black looks better in all these lines.

White attack is easily killed in this case


I assume Igor means 20.Ke2 when he writes:
Yes



But there is a big difference between 20.Ke2 h4 21.e5 and 20.e5. It is that after 20.Ke2 h4 21.e5 Bxe5 22.Bxh7 Kh8 23.Qg6 Bf5 24.Qh6 Bg7 25.Qxh4 Bxh7 26.Rh1 white wins.

Correct. As I said in my post, 20...Be5 is safer (in the tournament I wouldn't bother calculating 20...h4 anyway



The position after 20...Bxe5 might not be too bad for white. It is very fiddly and strategic, but at least both black bishops are tied down defending and the h-pawn is restrained.


Not quite. I'd say white's position is pretty much doomed after 20.Ke2 Be5 (at least strategically). White knight is pretty much meaningless and bishop is almost non-existent. If white keep the queens, he'll be eventually checkmated. Unfortunately, the endgame is pretty much lost (because of h pawn), especially if black keeps the rooks.
I'd say if black is over 2000 white has no reason to be optimistic.

Vlad
20-05-2009, 02:28 PM
I thought it was meant to be done without computer assistance.:cool:

Practically, to find the refutation for 22.Ne4... is not easy. Even Fritz 11 assesses the position for black as -1 even though white sacked a whole piece.

20.e5 Bxe5 21.Bxh7+ Kh8 22.Ne4 Ba4 23. Qd3 kh7 24. Kg7 Nd6 25. Nf5 Kg8 26. Ne7 Be8 27. Ng6 Bg6 28. Qg6 Bg7 29. d6...

Basil
20-05-2009, 02:55 PM
I thought it was meant to be done without computer assistance.:cool:
It is :wall: Anyone can plug in a box. The idea is to eek out what players of all strengths and personalities would do OTB. I always put the disclaimers but this time didn't.

I am enjoying the analysis and despite my comments above I am geting a feel for what different plaers would do and that's the most interesting. I will post:
1. What Patzer #1 :cool: thought OTB
2. What Patzer #1 did OTB
3. What Patzer #2 did OTB :lol:

Kevin Bonham
20-05-2009, 03:28 PM
Practically, to find the refutation for 22.Ne4... is not easy. Even Fritz 11 assesses the position for black as -1 even though white sacked a whole piece.

20.e5 Bxe5 21.Bxh7+ Kh8 22.Ne4 Ba4 23. Qd3 kh7 24. Kg7 Nd6 25. Nf5 Kg8 26. Ne7 Be8 27. Ng6 Bg6 28. Qg6 Bg7 29. d6...

Yes there is serious long-term compensation here.

Not being a Tromp player I didn't even look at that; I was immediately drawn to 20.e5 as a move that I thought was screaming out to be played and only when it started looking "falsified" did I switch to whether 20.Ke2 activating the rook first (since you have to do that anyway) might be better.


It is :wall: Anyone can plug in a box. The idea is to eek out what players of all strengths and personalities would do OTB. I always put the disclaimers but this time didn't.

Yes, I was aware of that but when I got to a direct question "Which side does an engine prefer" I assumed you were happy for the box to be plugged in at that moment.

Kevin Bonham
20-05-2009, 03:36 PM
If Black had played 19... Be5 instead, then I would really hate to be White; that Pe4 is in the way, as others have noted.

I think we need to know what black has taken on h5; it might be something larger than a pawn! :D


I'd say if black is over 2000 white has no reason to be optimistic.

I certainly wouldn't expect to hold white's position against a much stronger strategic player. But against my own level I wouldn't be that concerned.

Basil
20-05-2009, 04:06 PM
I think we need to know what black has taken on h5; it might be something larger than a pawn! :D
Indeed. Black had swung a rook from e8-e5-h5 looking for an exchange (which apart from neutralising white's v.strong rook h1) sought to create the passer currently part of the equation under discussion.

Capablanca-Fan
20-05-2009, 05:00 PM
Indeed. Black had swung a rook from e8-e5-h5 looking for an exchange (which apart from neutralising white's v.strong rook h1) sought to create the passer currently part of the equation under discussion.

Good point. But it would have been better to neutralize it from e7, and play Be5 blockading, then aim for ... b5. One R wouldn't be able to do much for White with all the other pieces on the other wing, with only a narrow gate on f1 to manoeuvre them to the K-side.

ER
20-05-2009, 11:15 PM
All my conceptual ideas were disgussed by strong players, Howie you are a witness:

IMHO, first things first, White cannot afford to allow the bloackade on e5, therefore 20.e5 is as good as any! At some stage (sooner rather than later) White must play Ne4, then the plan is to get the King out of the way, (...)
ok I stuffed up in the following:

move the R at g1 and the attack plays itself!
White is better!
but nobody 's perfect!

Davidflude
21-05-2009, 10:23 AM
20.e5 Bxe5 21.Bxh7+ Kh8 22.Ne4 Qd8 the queen races back to cover the black squares and then take part in the black counter attack.

This is more difficult for white. Are you going to move the knight or the bishop?

Igor_Goldenberg
21-05-2009, 01:57 PM
The position after 20...Bxe5 might not be too bad for white. It is very fiddly and strategic, but at least both black bishops are tied down defending and the h-pawn is restrained.


I actually missed 'x' and thought you referred to 20.Ke2 Be5 line.
After 20.e5 Bxe5 white indeed has more practical chances to hold. In the end blacks extra pawn must work, but with both kings open it's not straight-forward.
The 22.Ne4 line doesn't look dangerous to me, David's suggestion of 22...Qd8 (I would also follow it with Qe7) is good enough. Of course I just rely on gut feeling without calculating long lines or analysing it on the computer.

Kevin Bonham
21-05-2009, 02:04 PM
I actually missed 'x' and thought you referred to 20.Ke2 Be5 line.

No the x was an error on my part; I did mean the 20.Ke2 Be5 line. I think the 20.e5 Bxe5 line is pretty unpleasant for white although white might survive.

antichrist
22-05-2009, 02:44 PM
Gunnar, just as What Does Arbitar Do is my albatross, so is the Tromp your albatross

Basil
22-05-2009, 11:08 PM
5rk1/pp1b2bp/3p4/q1pP3p/2P1Pp2/2NB1P2/PPQ2P2/R4K2 w - - 0 19
That was all very edifying. Thank you to everyone who participated. Now that I've had the benefit of your minds, allow me to dilute the collective IQ of the board with mine :lol:

My Thoughts OTB
At the board, I recall being happy with the position (white).
I thought my king was going to have a safe home - my opponent's exposed.
I loved the career prospects of my knight.
I loved the long-term weaknesses of black's kingside pawns, not to mention his backward d pawn.

What I Failed To Appreciate OTB
The speed of the passer.
The various pluses discussed above are only weaknesses if I do something about them :doh:

What I Was Most Interested In From Commentary Here
That the better players preferred black. I'm assuming on the merits and not post-box-plugging-in.

What Was Played OTB
20. e5
Because
- I get the pawn back and loosen the opponent's king
- It was a case of now or never because the whole world was eyeing the blockading of e5 with the bishop
- My knight wanted e4 and g5 and even the idea of a whole piece sac a la Drug - I figured a marauding knight, queen and rook v an exposed king (slight oversimplification) was all good.
- I couldn't see anything better and could work it all out next move.
- It was at least active.

What I can Offer About Engines and Strong Play
The position, although imbalanced with the potential to uncoil, tends to drawish positions with good play from both sides (as far as my brief engine analysis goes).

Soon - a treat - being the game score :wall: :lol:

Basil
24-05-2009, 08:45 PM
Please be warned ... You are about to witness white completely busted ... and swindling a draw with invented ghosts and some barry. This is not a drill. Nor is it pretty and might offend some sensibilities.

1. d4 Nf6 2. Bg5 c5 3. Bxf6 exf6 4. d5 d6 5. c4 g6 6. e3 Bg7 7. Nf3 Nd7 8. h4 Ne5 9. h5 O-O 10. hxg6 fxg6 11. Nc3 Qa5 12. Be2 Nxf3+ 13. gxf3 f5 14. Qc2 Bd7 15. Kf1 f4 16. e4 Rae8 17. Bd3 Re5 18. Rh2 Rh5 19. Rxh5 gxh5 20. e5 Bxe5 21. Bxh7+ Kh8 22. Be4 Qd8 23. Ke2 h4 24. Rh1 h3 25. a3 Qf6 26. Kd2 Rg8 27. Kc1 Rg2 28. Nb5 Qh4 29. Bf5 Bxf5 30. Qxf5 h2 31. Qf8+ Rg8 32. Qf5 Rg1+ 33. Kc2 Qxf2+ 34. Kb3 Qh4 35. Qf8+ Rg8 36. Qf5 Rg2 37. Qf8+ Kh7 38. Nc7 Rxb2+ 39. Ka4 Rg2 40. Ne6 Qf6 41. Qe8 Kh6 42. Qc8 Rb2 43. Nf8 Qf7 44. Qh3+ Qh5 45. Qe6+ Kg7 46. Nd7
Qg6 47. Qe7+ Kg8 { DRAW } 1/2-1/2

Desmond
24-05-2009, 08:53 PM
I can't believe you got a draw out of that. Shirley, you can't be serious.

Kevin Bonham
24-05-2009, 09:04 PM
Thanks for the warning; I think it was necessary. :rolleyes:

It's not even a draw where he agrees to it. What is he afraid of, that you're going to force a draw? :wall:

Basil
24-05-2009, 09:27 PM
It's not even a draw where he agrees to it.
Black offered it and I accepted. I believe it is a draw at that point.

Time pressure again was a factor and there were a few traps for black to avoid floating around in the moves just prior. I'm sure he also didn't fancy fancy going from a won position to lost one. Funny game, chess.

Kevin Bonham
24-05-2009, 09:40 PM
Black offered it and I accepted. I believe it is a draw at that point.

I don't. He shouldn't have played ...Kg8, he should have played ...Kh6. So assuming (after ...Kg8) that you play 48.Qd8+ Kg7 49.Qe8+ now he can play ...Kh6. I may be wrong but I can see no draw after ...Kh6. Your only check is Qh4+ and after Qh5 your queen must swap off or make itself scarce. If Qe7 he can take on f3 and you can check his king all the way to g3 if you like but it won't save the position.

If you give it to the box, the box might say it is a draw, but this is probably only because some boxes are brain-damaged and give 0.00 for second appearances of the same position so that they don't waste resources calculating pointless repetitions.

Basil
24-05-2009, 10:17 PM
I don't. He shouldn't have played ...Kg8, he should have played ...Kh6.
Roger that. Thanks.

Saragossa
24-05-2009, 10:22 PM
15. Kd2 is a nice move and I think that if this move was played then white can claim to hold an advantage. And maybe even 0-0-0 would be a most probably unsound but still alright otb sac.

Igor_Goldenberg
26-05-2009, 03:26 PM
What I can Offer About Engines and Strong Play
The position, although imbalanced with the potential to uncoil, tends to drawish positions with good play from both sides (as far as my brief engine analysis goes).


Rare case where engine is inferior to protein player. Without 20.e5 decent player would beat an engine (I know it's hard to imagine:) )

About the game:
What about 29...Rxf2

Capablanca-Fan
26-05-2009, 05:31 PM
1. d4 Nf6 2. Bg5 c5 3. Bxf6 exf6 4. d5 d6 5. c4 g6 6. e3 Bg7 7. Nf3 Nd7 8. h4 Ne5 9. h5 O-O 10. hxg6 fxg6 11. Nc3 Qa5 12. Be2 Nxf3+ 13. gxf3 [why ruin the Ps? In the Tromp, White surrenders the B-pair to ruin the enemy Ps structure not his own.] 13... f5 14. Qc2 [White should play f4 himself to prevent the coming dark-square blockade] 14... Bd7 15. Kf1 f4 16. e4 Rae8 [Black should play 16... Be5, a6, Rab8 then launch b5. White would have no counterplay. The only K-side defence Black needs is ... Rf7; those doubled Ps prevent any more White pieces attacking the K-side] 17. Bd3 Re5 18. Rh2 Rh5 [this just gives White counterplay] 19. Rxh5 gxh5 20. e5 [well spotted; this P was just in the way] 20... Bxe5 21. Bxh7+ Kh8 22. Be4 Qd8 23. Ke2 h4 24. Rh1 h3 25. a3 Qf6 26. Kd2 Rg8 27. Kc1 Rg2 28. Nb5 Qh4 29. Bf5 Bxf5 30. Qxf5 h2 31. Qf8+ Rg8 32. Qf5 Rg1+ 33. Kc2 Qxf2+ 34. Kb3 Qh4 35. Qf8+ Rg8 36. Qf5 Rg2 37. Qf8+ Kh7 38. Nc7 Rxb2+ 39. Ka4 Rg2 40. Ne6 Qf6 41. Qe8 Kh6 42. Qc8 Rb2 43. Nf8 Qf7 44. Qh3+ Qh5 45. Qe6+ Kg7 46. Nd7
Qg6 47. Qe7+ Kg8 { DRAW } [as has been pointed out, Black should not have taken the draw here] 1/2-1/2


That the better players preferred black. I'm assuming on the merits and not post-box-plugging-in.
Not me. I don't even bother to use the engine for strategical assessments; I don't trust it. Conversely, when it comes to assessing a sharp position, including the final one, they are unbeatable, as long as they are allowed to analyze enough ply.

Capablanca-Fan
26-05-2009, 05:34 PM
15. Kd2 is a nice move and I think that if this move was played then white can claim to hold an advantage. And maybe even 0-0-0 would be a most probably unsound but still alright otb sac.
I have no idea what you mean.

Basil
26-05-2009, 07:31 PM
Rare case where engine is inferior to protein player. Without 20.e5 decent player would beat an engine
I believe it, baby!


Not me. I don't even bother to use the engine for strategical assessments; I don't trust it. Conversely, when it comes to assessing a sharp position, including the final one, they are unbeatable, as long as they are allowed to analyze enough ply.
Righteous.

Saragossa
26-05-2009, 11:49 PM
That most probably means that I'm wrong :wall: :P

btw these were somments on the entire game not analysis on the given position. All I saw in the given position was 1.e5 Bxe5 2. Bxh7+ Kh8 3. Ne4 but I scrolled down and found Durg having posted on it already.