Showing posts with label Stockfish. Show all posts
Showing posts with label Stockfish. Show all posts

Tuesday, January 7, 2020

The Database: Updated

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I recently updated The Database with games from the Free Internet Chess Server, through the end of 2019. The 62,000 games therin represent the largest collection of Jerome Gambit and Jerome-ish openings that I know of.

In addition, because 90+% of the games come from online club play (wins, losses and draws), they are pretty representative of the practical outcome of certain moves or lines. Players can consult their favorite computer (Stockfish, Komodo, Houdini, Crafty, etc.) to get an "objective" assessment of play, and then they can dip into The Database and see how well the lines have fared in play.

There are 15,036 games with the moves 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+, the main line Jerome Gambit.

There are 2,715 games with the moves 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4.Nc3 Bc5 5.Bxf7+, the Italian Four Knights Jerome Gambit.

There are 207 games with the moves 1.e4 e5 2.Nf3 Nc6 3.Bc4 h6 4.0-0 Bc5 5.Bxf7+ and 160 games with the moves 1.e4 e5 2.Nf3 Nc6 3.Bc4 h6 4.Nc3 Bc5 5.Bxf7+, both variants of the Semi-Italian Jerome Gambit.

There are 148 games with the moves 1.e4 e5 2.Nf3 Nc6 3.Bc4 h6 4.Nc3 Nf6 5.0-0 Bc5 6.Bxf7+, the Semi-Italian Four Knights Jerome Gambit.

There are 6,388 games with the moves 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nd4 4.Bxf7+, The Blackburne Shilling Jerome Gambit.

There are 2,470 games with the declination 1.e4 e5 2.Nf3 Nc6 3.Bc4 Na5.

There are 17,582 games with the moves 1.e4 e5 2.Bc4 Bc5 3.Bxf7+, the Abrahams Jerome Gambit.

That leaves about 17,500 miscellaneous games that are Jerome-related, primarily through an early Bxf7+. They are there both to give players ideas about the opening - an for entertainment purposes.

Wednesday, January 1, 2020

Jerome Gambit: The Deadly f-File

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In the following game, Black's initial moves give him good play. He relaxes too soon, however, and finds danger along the f-file - twice.

Wall, Bill - Guest2056949
PlayChess.com, 2019

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+


4...Kxf7 5.Nxe5+ Nxe5 6.d4



6...Bxd4 7.Qxd4 Qf6 8.Be3 Ng4


Give Black extra points for creativity. There is only one other game in The Database with this move - a blitz win for the second player.

9.Qb4 Nxe3 10.fxe3

Stockfish 10 sees Black with a winning game.

10...d6 

Ooops.

Won games don't win themselves.

Perhaps the game should have continued 10...Qh4+ 11.g3 Qe7 12.O-O+ Nf6, still good for Black.

11.Rf1 Qxf1+ 12.Kxf1 Nf6 13.Qc4+ Be6 14.Qxc7+ Kg6 15.Qxd6 Rae8 

White has a Queen and 3 pawns for a Rook and a Bishop. He can work up an attack on the enemy King, or continue to pick off material.

16.Nc3 Rhf8 17.Kg1 Ng4 18.Nd5 Kf7 19.Rf1+ Nf6 20.e5 Black resigned

The Knight, pinned along the f-file, is done for.

Thursday, December 26, 2019

Jerome Gambit: Sacrifice/Blunder?


A Jerome Gambit win, and some handy endgame play in another game, will allow me to move on to the 3rd round of play in both the "Italian Game Classic" and "Italian Game Battlegrounds" tournaments at Chess.com. There will be a bit of a wait, however, until I can play a few more Jerome Gambits, as each tournament has a number of games to complete before the round is finished.

The turning point in the following game reminds me of the light-hearted comment about giving up material: if it succeeds, it's a "sacrifice", if it fails, it's a "blunder". I would love to say that my chess has matured to the point where I made an intuitive sacrifice, but I have to admit that it was more of a fortunate oversight.

perrypawnpusher - mallack
Italian Game Battlegrounds, Chess.com, 2019

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 




4...Kxf7 5. Nxe5+ Nxe5 6. Qh5+ Kf8



The Jerome Defense, first suggested by Alonzo Wheeler Jerome in an article in the Dubuque Chess Journal of July, 1874, and seen, initially, in Jaeger - Jerome, correspondence, 1880 (1-0, 40).

The Database has 665 game examples, with White scoring 50%. My own experience is a bit better: in 36 games, I scored 79%. (That probably reflects experience with the line.)

7.Qxe5 d6 8.Qg3 

As I noted in an earlier post
I experimented with Jerome's 8.Qf4+ in perrypawnpusher - Capt. Mandrake, Jerome Gambit 3 thematic tournament, ChessWorld.com, 2008 (1-0, 9) and perrypawnpusher - LeeBradbury, "Italian Game" Thematic, Chess.com, 2012 (1-0, 36).
I also tried 8.Qc3 in perrypawnpusher - Raankh, blitz, FICS, 2009 (0-1, 22).
There is not much difference in the strength between these two moves and the text, or even 8.Qh5, if Stockfish 9 is to be believed.

8...Nf6 9.Nc3 

I am not sure why I chose the text move over 9.d3. Before this game, I was 3 - 1 with 9.Nc3 and 5 - 1 with 9.d3. The two lines sometimes transpose, and 9.d3 brings White one step closer to resolving the issue of Black's annoying dark square Bishop, so, perhaps it should be played first.

9...Be6 

This was also played by Abhishek29 against me earlier this year. The move is good, and preserves Black's advantage, although it has the slight taint of placing the Bishop (possibly) in a place where an advancing White f-pawn might hit it.

10.O-O g6 

This move, a novelty, according to The Database, does several things. It resists a possible f2-f4-f5 by White; it protects the Black g-pawn from White's Queen, and it gives the Black King a place to step out of the way, to castle-by-hand and allow his Rook to get into play.

11.d3 Kg7 12.Na4 

Seriously?!

I was going to try this move, after the trials of my game against warwar, in the 3rd round of the Italian Battleground tournament (at Chess.com) earlier this year? Sure, the positions are not the same, but warwar did not meekly retreat his Bishop to b6, he brought it to d4, then e5 - and then threw in ...Nh5 for good measure. It was a messy game, even if I did weasel out a win.

Then, there was the additional anxiety related to my game against Abhishek29, when he did retreat the Bishop, and I was able to exchange it off.

Certainly, it was a time for in-depth concrete analysis - so, of course, I crossed my fingers for luck and just made the Knight move...

12...Bb6

Whew!

After the game, Stockfish 10 pointed out that 12...Bd4 13.c3 Be5 14.f4 would be hit by 14...Nh5. In fact, 13...Nh5 would have been good for Black, too. Yikes.

13.Nxb6 axb6 14.f4 Rxa2 

This took me by surprise. It should not have - in a similar position against Abhishek29, I had prevented the capture by playing a2-a3. But, is the loss of the pawn a big deal, any way? It turns out, it is not. This is the sacrifice/blunder of material that I referred to in the introduction to this game.

15.Rxa2 Bxa2 16.b3 

Black's Bishop has left his King, and is trapped. It is vulnerable to capture in a couple of moves, which explains Black's next choice.

16...Qa8 

In for a penny, in for a pound.

Black has grabbed the pawn, and now feels the need to protect the locked-in Bishop, even at the cost of removing another defender from the Kingside.

17.Bb2

This move reminded me of a booklet on the 2.b3 Sicilian that I bought in 1977, from Ron's Postal Chess Club, of all places. At the time, I was advancing the b-pawn one step against 1...c5 if I was feeling conservative, or two steps (the wing gambit) if I was feeling rowdy; and I even tried 2.b3 against the French and Caro Kann defenses. Nowadays you can find Sabotaging the Sicilian, French & Caro-Kann with 2.b3 by Jerzy Konikowski and Marek Soszynski.

Oh - back to the game. White's attack is about to come together.

17...Rf8 18.f5 

18...Qa5 19.fxg6 hxg6 20.Qf4 g5 21.Bxf6+ 

After the game, Stockfish 10 preferred 21...Qg4. I wanted my piece back, right away.

21...Kg8 22.Qg4 Qd2 

Black's Queen cannot save the day.

23.Bxg5 Black resigned



You probably saw the cute checkmate, instead, with 23.Qe6+ Kh7 24.Qe7 Rf7 25.Qxf7+ Kh6 26.Qg7+ Kh5 27.Qh7+ Kg4 28.Qh3#.

Please note the stranded Bishop on a2.

Tuesday, December 24, 2019

Jerome Gambit: Merry Christmas!

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Here is my latest letter from Cliff Hardy - a Jerome Gambit game (time limit: bullet, one minute, no increment - in this game, about a second per move.) with a timely Christmas motif! I have added some diagrams, but the commentary is all his - Rick

Merry Christmas, Rick!

This game intrigued me as Black was unusual in being able to find the excellent 11...Kc6! move in this variation. Unfortunately, he was forced soon after that to become really generous this Christmas, as the presents began to be handed out...

Cliff Hardy (2286) - NN (2532)
1 0, Lichess, 2019

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 


4...Kxf7 5.Nxe5+ 

If you expect to receive presents, you should give some first!

5...Nxe5 6.Qh5+ Ke6 

7.Qf5+ Kd6 8.f4 Qf6 9.fxe5+ Qxe5 10.Qf3 Nf6 


11.d3 Kc6!

Very rare for someone to find this risky-looking but pugnacious move - and in bullet too!

12.Nc3

I'm never quite sure in this variation whether to play c3 or Nc3.

12...d5 13.Bf4 dxe4 14.dxe4 Qe6??


Black gives a Christmas present! 14...Qh5! -++, intending 15.e5+ Qxf3 16.gxf3 Nh5, would have been very strong for him.

15.0-0-0?? =

It's Christmas time and White proves to be very charitable! I didn't realise that 15.e5+ Nd5 ++- doesn't really hang in for Black e.g. 16.0-0-0 Rd8 17.Nxd5 Rxd5 18.c4, when the pinned Black rook will require wrapping paper and a gift tag.

15...a6?? ++- 

You know that moment at Christmas when you graciously refuse a Christmas present but the giver continually thrusts it upon you? A complex game would have arisen after 15...Qg4! 16.Qf1! (threatening checkmate in one with 17.Qb5#) 16...b6 =, when Black's exposed king compensates for White's sacrificed bishop.

16. e5+ Kb6 17. exf6 Qxf6??


Another present for me? Why, thank you! Stockfish rated the position before this move as lost for Black anyway, due to his exposed king, but I admit it all looked very unclear to me! Now though, it was fairly easy to take out the win and the rest of the game was uneventful.

18.Nd5+ Ka7 19.Nxf6 gxf6 20.Qc3 Bb6 


21.Be3 Bg4 22.Bxb6+ cxb6 23.Rd6 Bf5 24.Qxf6 Rhf8 25.Qd4 Rac8 26.Qxb6+ Ka8 27.c3 Be4 28.Rhd1 Bxg2 29.Rd8 Kb8 30.Rxf8 Rxf8 31.Rd8+ Rxd8 32.Qxd8+ Ka7 


33.Qd4+ Kb8 34.Qg7 Bc6 35.Qxh7 Ka7 36.Qh8 a5 37.h4 Kb6 38.Qd4+ Kb5 39.h5 a4 40.h6 a3 41.b3 Ka6 42.c4 Be4 43.h7 Bxh7 44.Qd5 Ka7 45.Qb5 Bg8 46.Qa5+ Kb8 47.Qd8+ Ka7 48.Qxg8 Kb6 

49.c5+ Kxc5 50.Qc4+ Kb6 51.Qa4 Kc5 52.Qxa3+ Kd4 53.Qa4+ Kc5 54.Qc4+ Kb6 55.b4 Ka7 56.Qc5+ Kb8 57.Qb5 Ka7 58.a4 b6 59.a5 Kb7 60.Qxb6+ Kc8 61.a6 Kd7 62.Qb7+ Ke8 63.a7 Kd8 64.a8=Q checkmate

Sunday, December 22, 2019

Jerome Gambit: Themes

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The following game is chock full of Jerome Gambit moves and themes. It is an enjoyable argument for adding that "refuted" opening to your repertoire, if only for light entertainment.

Wall, Bill - Guest2047860
PlayChess.com, 2019

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 



4...Kxf7 5.Nxe5+ Nxe5 6.d4 



What to do about the pawn fork? The simplest idea is 6...Bxd4, giving back a piece for a pawn. Black opts for something a bit more complicated.

6...Bb4+ 7.c3

Now, what?

Well, The Database suggests 7...Qh4!?, which has 13 wins for Black, against 2 losses, although it is fair to point out that those 2 wins for White were by Bill Wall.

Or, the Knight can retreat with either 7...Nb6 or 7...Nc6, giving up the Bishop.

Or the Bishop can retreat with 7...Be7, giving up the Knight.

With an imaginary smile on its face, Stockfish 10 suggests that even 7...Bc5 leads to Black's advantage.

7...Bxc3+ 

Giving up the piece for a pawn, after all, leading to a position where he has an edge.

8.Nxc3 

8...Ng6 9.O-O c6 

Black senses that Winter is coming, and takes early steps to limit White's developing pawn center.

It is interesting to note that The Database has no examples of either 9...d5 or 9...h5, Stockfish 10's recommendations. Maybe, I should give the alternative title of "Jerome Gambit Secrets #11" to today's post?

Jerome Gambit theory continues to expand and evolve. You, too, can add to it

10.f4 d6 

White goes through his checklist: pawn center, Rook on f-file, enemy King on f-file, actual enemy piece to kick with a pawn, possible pawn break in the center... 

11.f5 N6e7 12.Bg5 

Another thematic Jerome Gambit move, although it is usually aimed at a Knight at f6, not e7. In fact, Komodo 10 now suggests that Black "remedy" this situation with 12...Nf6, with an even game.

12...h6

It is natural to challenge a pin immediately, but, in this case, this is a mistake - encouraging another thematic Jerome Gambit move.

13.Qh5+ Kf8 14.f6 

The hits just keep on coming.

14...g6 

Leading to a delightful ending, but the stronger defense, 14...Nxf6, falls to 15.Bxf6, and White's heavy pieces will win the day.

15.fxe7+ Ke8 16.exd8=Q checkmate



Wednesday, December 18, 2019

Jerome Gambit: Another Day In The Life Of

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Here is another (see "Jerome Gambit: Full-Bodied Defense") Jerome Gambit game which should be routine and boring. Black makes a mistake on move 7, turning his clear advantage into a clear disadvantage. In fact, this had happened twice before in Bill Wall games, and they showed "1-0" in 10 moves or less (in a third game, Black struggled on for 10 more moves).

So, Bill takes his advantage and moves on to the win. Things were not that simple, though. Watch.

Wall, Bill - Anonymous
lichess.org, 2019

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 




4...Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Ke6 7.f4 g6



It is fun, kicking White's Queen. However, this move gives up the Knight at e5 and the Rook at h8. (If you worry about being greedy, you can substitute capturing the Bishop at c5.)

8.Qxe5+ Kf7 9.Qxh8 

Here, Black resigned in Wall, Bill - DGTS, FICS, 2011

9...Qh4+ 10.g3

Here, Black resigned, in Wall, Bill - Guest1681797, PlayChess.com, 2013,

10...Qh3

Or 10...Qf6 11.Qxh7+ Qg7 12.Qxg7+ Kxg7 13.Nc3 d6 14.Nd5 Bb6 15.b3 Bg4 16.Bb2+ Kh7 17.Nxb6 axb6 18.Kf2 Re8 19.h3 Be6 20.g4 Black resigned, Wall, Bill - Guest862403, Play.Chess.com 2014.

11.d3 d5 

So, here we go. White is up the exchange and a couple of pawns. His Queen is a bit uncomfortable in the corner, at h8, however, and his King is not altogether safe. What to do?

12.Qe5 

Perfectly reasonable. Anyone who has ever seen Amateur - Blackburne, London, 1884 (see "Nobody expects the Jerome Gambit!" and "Jerome Gambit: Dr. Harding Checks In") would not wait for ...Nf6, locking in White's Queen.

Now, White goes on to win in three dozen more moves.

But - wait. Stockfish 10, recommends, instead, 12.f5!?, with a whole lot of crazy tactics -  12...Bxf5 (not 12...gxf5 because of 13.Nd2 dxe4 14.Nxe4!? fxe4 15.Rf1+ and attack) 13.Qe5 and the f-file will be trouble for Black, especially after ...Qg2 is met by Rf1. Just one example of play is 13...dxe4 14.Qxc5 exd3 15.Qxc7+ Kf8 16.Qc5+ Kg7 17.Nc3 Qg2 18.Rf1 dxc2 19.Be3 Re8 20.g4 Qxg4 21.Kd2 - and you can see why Bill simply chose to remove his Queen!

12...c6

Black supports his d-pawn - but Stockfish 10 will have none of it. To keep only about a three-fourths of a pawn behind, Black should try 12...Qg2 13.Rf1 Bg4!? 14.Qxd5+ Kg7 15.Nc3 b6!? when 16.f5 Nf6!? 17.Qc4 (not 17.Qxa8? Bd4! with a forced mate) Qxh2 18.d4 Qxg3+ 19.Rf2 Qg1+ 20.Qf1 Qxf1+ 21.Rxf1 Bxd4 22.fxg6 hxg6 23.Nb5 Be5 24.Bf4 Bxf4 25.Rxf4 g5 26.Rf1 Nxe4 27.Rg1 Nf6 leaves Black with a pawn for the exchange...

So - Black's choice of a move is understandable, too.

13.f5 gxf5 14.Nd2 Nf6 15.Nf3 Qg2 16.Rf1 Qxc2 



It is humorous to point out that Stockfish 10 sees White as being the equivalent of 4 pieces ahead. I am not sure that Bill's King felt that way!

17.Ng5+ Kg7 18.Bd2 Qxd3 19.exf5 

This will support White's Knight when it comes to e6. For sheer madness, take a look at 19.Rf3 Qc4 20.Rf4 

19...h6 20.Ne6+ Bxe6 

21.fxe6

This is fine, altough Stockfish 10 recommends 21.O-O-O!? Qc4+
22.Bc3 Bd4 23.Qxd4 Qxd4 24.Rxd4 Bg8 when White would still be up the exchange.

21... Bd4 22.Qc7+ Kh8 23.O-O-O Qc4+ 24. Kb1 Ne4 25. Bc1 Qb4 

26.e7 

Cold blooded. Others might have returned the exchange with 26.Rxd4 to deal with one threat to b2, or tried 26.Ka1 to avoid the nasty 26...Nc3+ fork. Instead, Bill enlists the "Jerome pawn" in his checkmate threats.

26... Nc3+ 27.Ka1 Nxd1 28.Qd8+ Rxd8 

Abject surrender, although 28...Kh7 29.Rxd1 Bg7 30.Qxa8 Qxe7 would also leave him a Rook down. 

29.exd8=Q+ Kg7 

30.Qd7+ Kh8 31.Qe8+ Kh7 32.Rf7+ Bg7 33.Qd7 Qd4
34.Qf5+ Kg8 35.Re7 Qf6 36.Re8+ Kf7 37.Qh5+ Qg6 38.Re7+ Black resigned

He will soon be down a Queen for a few pawns.