Saturday, July 11, 2015

Footnotes to More Exploring

Here are some additions to the previous post, which focused upon a line in the  Abrahams Jerome Gambitthe game ndizvoh - stevebrown, blitz, FICS, 2015.

After 1.e4 e5 2.Bc4 Bc5 3.Bxf7+ Kxf7 4.Qh5+ g6 5.Qxe5 Bxf2+ 

the move 6...Nf6 was suggested as an alternative to 6...Qf6,

He also had the move 6...Nf6, which does the same thing, as 7.Kxf2 would then be met with 7...Ng4+, winning White's Queen.
Examples from The Database: 

Rattymouse  - bobbybo

blitz, FICS, 2007
1.e4 e5 2.Bc4 Bc5 3.Bxf7+ Kxf7 4.Qh5+ g6 5.Qxe5 Bxf2+ 6.Ke2 Nf6 7.Kxf2 Ng4+ White resigned

lksharma - oeyvind

blitz, FICS, 2008
1.e4 e5 2.Bc4 Bc5 3.Bxf7+ Kxf7 4.Qh5+ g6 5.Qxe5 Bxf2+ 6.Ke2 Nf6 7.Kxf2 Ng4+ 8.Ke1 Nxe5 9.d3 Rf8 10.Nh3 Kg8 11.Bg5 Qe8 12.Nd2 d5 13.Ke2 Bxh3 14.gxh3 dxe4 15.Nxe4 Nc4 16.Raf1 Rxf1 17.Rxf1 Nc6 18.Kd1 Nxb2+ 19.Kc1 Qe5 20.Nf6+ Kg7 21.Nd7 Qd6 22.Bf6+ Kh6 23.Bxb2 Qxd7 24.Bc3 Re8 25.Bd2+ g5 26.h4 Kh5 27.Bxg5 Re2 28.Bf6 Qg4 29.Kb2 Qb4+ 30.Kc1 Qa3+ 31.Kd1 Rxh2 32.Rf5+ Kg6 33.Rf4 Rg2 34.Bb2 Rg1+ 35.Ke2 Qe7+ White forfeited on time

xreal - jgknight

blitz, FICS, 2010
1.e4 e5 2.Bc4 Bc5 3.Bxf7+ Kxf7 4.Qh5+ g6 5.Qxe5 Bxf2+ 6.Ke2 Nf6 7.Kxf2 Ng4+ 8.Ke2 Nxe5 9.Nf3 Nxf3 10.gxf3 d5 11.d3 dxe4 12.fxe4 Bg4+ 13.Kd2 Qg5+ 14.Kc3 Qe5+ 15.Kb3 Be6+ 16.c4 Nc6 17.Rf1+ Ke8 18.Bf4 Nd4+ 19.Kc3 Ne2+ 20.Kd2 Nxf4 21.Nc3 Rf8 22.Ke3 Ng2+ 23.Kd2 Rxf1 24.Rxf1 Qg5+ 25.Kc2 Ne3+ 26.Kb3 Nxf1 White resigned

marciprevi - chesssuperstar

blitz, FICS, 2014
1.e4 e5 2.Bc4 Bc5 3.Bxf7+ Kxf7 4.Qh5+ g6 5.Qxe5 Bxf2+ 6.Kf1 Nf6 7.Kxf2 Ng4+ 8.Ke2 Nxe5 9.d4 Nc4 10.b3 d5 11.bxc4 Bg4+ 12.Ke3 Qg5+ 13.Kd3 dxc4+ 14.Kxc4 Qxc1 15.Kc3 Bd1 16.Ne2 Qxc2+ 17.Kb4 a6 18.Rf1+ Kg7 19.Na3 Nc6 checkmate

A little further along in the game's notes, I recommended that

White probably should have settled for 7.Qxf6+ Nxf6 8.Kxf2 Nxe4+ and a roughly equal game.
However, a quick look at The Database showed that in 23 games my suggestion scored 72% for Black!?

A consultation with Houdini 3 and Stockfish 6 gave me a clue as to what was going on. While both computer programs agreed that the responses 9.Ke1 and 9.Kf1 led to a balanced game, the move 9.Ke2 (3 games) led to an edge for Black, and the move 9.Ke3 (15 games) led to  an advantage for Black. (Both moves are well met by 9...Re8.)

It can be helpful to know what has been played previously, if only to know what moves to avoid!

Finally, it can be noted that after the game continuation, 1.e4 e5 2.Bc4 Bc5 3.Bxf7+ Kxf7 4.Qh5+ g6 5.Qxe5 Bxf2+ 6.Ke2 Qf6 7.Qd5+ Kg7

The Database contains 7 games with this position: 6 losses for White (one of them ndizvoh - stevebrown, blitz, FICS, 2015) and 1 draw.

Thursday, July 9, 2015

More Exploring

I have been doing some more exploring of the Abrahams Jerome Gambit - 1.e4 e5 2.Bc4 Bc5 3.Bxf7+ - (see "Exploring" for an earlier exploit) and the results have been puzzling, but worth reporting.

One important difference between the Abrahams Jerome and the regular Jerome Gambit is the value of ...Bxf2+ for Black. In the latter, the move serves mostly a "psychological" purpose (You sacrificed a piece to upset my King, so I will sacrifice a piece to upset your King), as discussed in "Trading Down Against the Jerome Gambit" and earlier posts. However, in the former, the return Bishop sacrifice is often the best move available.

ndizvoh - stevebrown

blitz, FICS, 2015

1.e4 e5 2.Bc4 Bc5 3.Bxf7+ 
Kxf7 4.Qh5+ g6 5.Qxe5 

A quick look in The Database shows 4,097 games have reached this position, with White scoring 53%. Only 1,151 games include the "best" response, 5...Bxf2+, which reduces White's scoring to only 52%.

Clearly there are other factors than the "best" move affecting the outcome!

A comparison with the Abrahams Jerome Gambit line 1.e4 e5 2.Bc4 Bc5 3.Bxf7+ Kxf7 4.Qh5+ Kf8 5.Qxe5 is even more puzzling. The Database has 5,026 games reaching this position, with White scoring 41% (suggesting that 4...Kf8 might be a stronger response than 4...g6). Yet, in the 219 games where Black makes his "best" response, 5...Bxf2+, White improves his scoring to 47%.

It's worth repeating: Clearly there are other factors than the "best" move affecting the outcome!


Black sees he will be losing his Bishop, and decides to get a pawn for it.


Declining the Bishop is rare, according to The Database, and not a good idea.  One example: KevinSI - stevebrown, standard, FICS, 20146.Kf1 Qf6 7.Nf3 Qxe5 8.Nxe5+ Ke6 9.Kxf2 Kxe5 10.Re1 Nf6 11.d3 Rf8 12.Kg1 Nc6 13.Nd2 Nd4 14.Nc4+ Ke6 15.Rf1 Kf7 16.Bg5 Kg7 17.c3 Ne6 18.Bxf6+ Rxf6 19.Rxf6 Kxf6 20.Rf1+ Kg7 21.Ne5 d6 22.Rf7+ Kg8 White resigned


Black protects his Bishop and Rook. He also had the move 6...Nf6, which does the same thing, as 7.Kxf2 would then be met with 7...Ng4+, winning White's Queen. 

7. Qd5+

White probably should have settled for 7.Qxf6+ Nxf6 8.Kxf2 Nxe4+ and a roughly equal game.

7...Kg7 8.Nf3 Ne7 9.Qc4 Bb6 

Black has retained his extra piece. White has an extra pawn, but given the lack of safety of his King, it is not adequate compensation.

10.Rf1 d6 11.Nc3 Bg4 12.Nd5 Nxd5 13.Qxd5 c6 14.Qc4 Re8 15.d3 d5 16.e5 Rxe5+ White resigned

Tuesday, July 7, 2015

A Discussion Continued

After this game was finished, I checked with The Database, and discovered that my opponent and I had "discussed" this opening (over the board) several times previously.

In addition, before I post a game on this blog, I usually "discuss" it with either Houdini 3 or Stockfish 6, hoping for enlightenment.

This time, however, my two electronic "friends" did not always agree in the early stages, occasionally sounding like a couple of know-it-all kibitzers, leaving a current assessment of the opening lines a bit unsettled.

Ironically, the game was tipped by the endgame play of both me and my opponent - as HAL 9000 once said, "It can only be attributable to human error."

perrypawnpusher - michon

blitz, FICS, 2015

1.e4 e5 2.Nf3 Nc6 3.Bc4 Nd4 4.Bxf7+ 

The Blackburne Shilling Jerome Gambit.


My opponent declined the piece a couple of times, a couple of years ago, with 4...Ke7, but without success: perrypawnpusher - michon, blitz, FICS, 2013 (1-0, 8) and perrypawnpusher - michon, blitz, FICS, 2013 (1-0, 41). 

5.Nxe5+ Ke8 

Instead, 5...Ke6 was seen in perrypawnpusher - michon, blitz, FICS, 2014 (1-0, 23); while 5...Ke7 was seen in perrypawnpusher - michon, blitz, FICS, 2013 (1-0,18). 


This move was preferred by Houdini 3 after some deep thought.

Some human input: In over 70% of the over-2,100 relevant Blackburne Shilling Jerome Gambit games in The Database, White chose 6.Qh5+, scoring 60%.

Instead, Stockfish 6 preferred 6.c3.

Again: In 21% of the relevant Blackburne Shilling Jerome Gambit games in The Database, 6.c3, was the people's choice, scoring 55%.

I checked, and noticed that 6.c3 was first mentioned on this blog in "Blackburne Shilling Jerome Gambit", 7 years ago.

Interestingly, an earlier version of Stockfish expressed a preference for 6.c3 about 5 years ago.

The choice of 6.Qa5+ or 6.c3 still seens to be an "Unfinished Discussion" (posted 3 years ago), although it seems that 6.c3 may have appeared in more blog posts than 6.Qh5+.

Here are a couple of examples of the 6.c3 Nc6 7.Nxc6 dxc6 8.d4 Qh4 line suggested by Stockfish 6: 9.0-0 (9.g3 Qxe4+ 10.Qe2 Qxe2+ 11.Kxe2 Bg4+ 12.f3 Bf5 13.Re1 Bxb1 14.Kf1+ Be7 15.Rxb1 Kd7 16.Re2 Re8 17.Be3 Nf6 18.c4 Rhf8 19.b4 Ng4 20.Kg2 Nxe3+ 21.Rxe3 Bxb4 22.Rxe8 Rxe8 23.Rxb4 Re2+ 24.Kh3 Rxa2 25.Rxb7 Ra4 26.Kg4 Rxc4 27.Rxa7 Rxd4+ 28.f4 c5 29.Ra8 c4 30.Rh8 c3 31.Rxh7 c2 32.Rxg7+ Kc6 33.Rg6+ Rd6 34.f5 c1Q 35.Rxd6+ cxd6 36.f6 Qc4+ 37.Kf5 Qf1+ 38.Ke6 Qh3+ 39.Ke7 Qd7+ 40.Kf8 d5 41.f7 d4 42.Kg8 Qg4+ 43.Kh8 Qh5+ 44.Kg8 Qg6+ 45.Kf8 d3 46.Ke7 Qxf7+ 47.Kxf7 d2 48.h4 d1Q 49.h5 Qxh5+ White resigned, marinrouge - homerg, FICS, 2002) 9...Ke7 10.Nd2 Nh6 11.Nf3 Qh5 12.Qd3 Kd8 13.Bg5+ Be7 14.Bxh6 gxh6 15.Ne5 Bd6 16.Qg3 Be6 17.f4 Bxe5 18.fxe5 Rg8 19.Qf3 Bg4 20.Qf7 Qxf7 21.Rxf7 Kc8 22.Kh1 b6 23.Raf1 Kb7 24.Rxh7 h5 25.Rff7 Rac8 26.d5 cxd5 27.exd5 Be2 28.d6 Rgf8 29.Rxc7+ Rxc7 30.Rxc7+ Ka6 31.h3 h4 32.Kh2 Bb5 33.Rg7 Bc6 34.e6 b5 35.d7 Rf6 36.Re7 Bd5 37.d8Q Rg6 38.Qc8+ Ka5 39.Qc7+ Ka4 40.Rg7 Rxg7 41.Qxg7 a5 42.Qd4+ b4 43.cxb4 Black lost on time, dzomba - VendettaA, lightning [!], FICS, 2006. 

6...g6 7.Nxg6 


Here we have another dispute.

Stockfish 6 prefers 7...Nxc2+, suggesting that after 8.Kd1 hxg6 (8...Nxa1? 9.Nxh8+ Ke7 10.Qe5#) 9.Qxg6+ Ke7 10.Qg5+ (Houdini prefers 10.Kxc2 with an edge for White) 10...Ke8 11.Qg6+ Ke7 12.Qg5+ White draws by repeating the position (Houdini prefers 12.Kxc2 with an edge for White).


A number of years ago I got away with the weaker 8.Qxh8?! after 8...Nh6 when 8...Nxc2+, instead, would have led to an edge (Houdini) or an advantage (Stockfish 6) for Black after 9.Kd1 Nxa1 10.Qxg8 in perrypawnpusher - tampajake, blitz, FICS 2009 (1-0, 12).

8...Ke7 9.Qg5+ Nf6

Here Stockfish 6 says Black has the advantage, while Houdini 3 says the position is equal.

Both prefer the text to 9...Ke8  of perrypawnpusher - adamzzzz, blitz, FICS, 2009 (1-0, 39). 


Better than 10.e5 of perrypawnpusher - JokeritT, blitz, FICS, 2010 (1-0, 28).


Stockfish 6 slightly prefers 10...Ke8 to the text, while Houdini 3 thinks 10...d6 is better. 

11.Qxd4 Be6 

Here, Houdini 3 likes White, while Stockfish 6 prefers Black.

Of course.

For the record, I have also seen:

11...c5 in perrypawnpusher - foreverblackman, blitz, FICS, 2010 (1-0, 21) and perrypawnpusher - vlas, blitz, FICS, 2010 (0-1, 23);

11...Qd7 in perrypawnpusher - theferno, blitz, FICS, 2010 (1-0, 28);

and 11...Bg7 in perrypawnpusher - Raankh, blitz, FICS, 2010 (1-0, 49). 


Also possible is 12.f4 c5 when again Houdini 3  likes White, while Stockfish 6 likes Black.

12...Bh6 13.d3 Bxc1 14.Rxc1

Both Stockfish 6 and Houdini 3 suggest 13...c5 first, to displace the White Queen.  

White has four pawns for his sacrificed piece. Even if the position is "objectively" even, his prospects are good at club play level.

The next few moves show that both players are blind to some tactical possibilities, however.

14...Qg8 15.g3 Bh3 16.Nd5+?! Nxd5 17.Qxd5? Qxd5 18.exd5 Rae8 

Both players overlook the fork 18...Bg2! when Black can grab a pawn and increase Kingside pressure after 19.Rg1 Rxh2 20.c4 Rf8.

19.Kd2 Kd7 20.c4 Re7 21.f4 Rhe8 22.Rce1 Rxe1 23.Rxe1 Rxe1 24.Kxe1

Both computer programs see the position as equal.

What follows goes along with suggestion that a bad plan is better than no plan at all - which is a nice way of saying that my bad idea worked, while my opponent missed some good ideas.

24...Bg4 25.Kf2 Ke7 26.Kg2?! Kf6?! 

Black is worried about stopping the Kingside pawns, when he probably should look at using his Bishop to capture a couple of center pawns: 26...Be2 27.d4 Bxc4 28.a3 Bxd5+ 29.Kf2 b6. After this, Black can look to create his own passed pawn, which should counter White's activity.

27.h3 Bd7?!

Again, 27...Be2 was to be preferred. Black's Bishop has to cut down the number of enemy pawns before they become a real problem. 

28.g4 Bxg4

This is tantamount to resignation. White can now develop play on both wings. At least one passer is bound to get through.


29...a6 30.Kf3 c5 31.dxc6 bxc6 32.Ke4 Kg6 33.d4 a5 34.b3 Kf6 35.a3 Kg6 36.b4 

Black resigned

Sunday, July 5, 2015

Coffee, please...

Image result for free clipart coffee

The other day I woke up too early, and said to myself, "Let's have a chess game, and then a cup of coffee."


I needed the coffee first.

perrypawnpusher - igisr
blitz, FICS, 2015

1.e4 e5 2.Nf3 Nc6 3.Bc4 h6 

The Semi-Italian Opening.

4.0-0 Bc5 5.Bxf7+ 

The Semi-Italian Jerome Gambit.

5...Kxf7 6.Nxe5+ Nxe5 7.Qh5+ Ng6 8.Qd5+ Ke7 

I have played games where Black has chosen 8...Ke8, 8...Kf8 and even 8...Kf6, but the text move was new to me. (There is only one game example in The Database.)

There is something significant about the placement of the Black King, but in the morning mental fog, it eluded me.

9.Qxc5+ d6 10.Qe3 Nf6 11.f4 Re8 

Instead, the game mrddblack - ammagamma (1-0, 32), continued 11...Rf8

12.f5 Ne5 13.d4 Nc4 

Routine, but probably better was 13...Nc6.

14.Qd3 b5 15.Nc3

After the game, Stockfish recommended the straight-forward 15.b3 Nb6 16.e5 dxe5 17.dxe5 Qxd3 18.exf6+ Kxf6 19.cxd3 with a slight advantage for White.

The text move is not "wrong", but it reflects the fact that I believed that e4-e5 was not currently playable because it allowed the exchange of Queens - missing, as Stockfish showed, that White can use the zwischenzug exf6+ after ...Qxd3 to regain his sacrificed piece.

15...a6 16.b3 Nb6 17.Ba3

Hoping that the pin on Black's d6 pawn will allow White's e-pawn to advance, but this is cloudy thinking, and easily evaded. Better was the simple 17.e5 dxe5 18.dxe5 Qxd3 19.exf6+ Kxf6 20.cxd3 as we have seen.

17...Kf7 18.Rae1

A standard move in this kind of position, but I could not escape the feeling that I had missed something...

18...Bb7 19.Bb2 b4 

White's pawn center is now crumbling under the pressure of Black's pieces (and the b-pawn), but I was confident that I had everything under control.

20.Qc4+ Nxc4

Or not. White resigned.

I had a cup of coffee while I did the post mortem.