Saturday, January 13, 2018

Jerome Gambit: Choosing Better or Worse?

Sometimes a computer chess engine will recommend a line of play which is "objectively" better than an alternative that a human might choose. Yet there might be good reasons to choose the "worse" line of play, if it is tricky and has some traps. See the note to Black's 7th move.

On the other hand, sometimes "human" moves fall short, as well. See the note to Black's 9th move.

Wall, Bill - Guest902091
PlayChess.com, 2017

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 



4...Kxf7 5.Nxe5+ Nxe5 6.d4 Nf6 



Black has so many ways to return some of the sacrificed material!

7.dxe5 Bxf2+ 

This move appears in 10 previous games appearing in The Database, with White scoring 70%. However, that is not the whole story.

Stockfish 8 recommends, instead 7...Qe7!?, which does not show up in any of the games in The Database. White does best to grab a second piece with 8.exf6, but then is faced with how to answer 8...Qxe4+.

Probably best is 9.Kf1 which we will come back to in a moment, after first examining the messy 9.Be3.

Black can respond to this latter move with 9...Bxe3 10.fxe3 Qxe3+ 11.Qe2 when the exchange of Queens would leave him a pawn up. Or he could go for 11...Qc1+ when 12.Kf2 is the offer of a Rook, i.e. 12...Qxh1, although it does not turn out well for the second player: 13.Qe7+ Kg6 14.Qxg7+ Kf5 15.Nc3 Qxh2 (taking the other Rook with 15...Qxa1 leads to mate) 16.Rf1 and Black's position is miserable as he has only 16...Qf4+ to help him extend the game, but 17.Kg1 Qxf1+ 18.Kxf1 still is hopeless. After visiting c1, Black's Queen should return to f4 with check, and eventually wind up a pawn ahead, again. 

Going back to the computer-recommended 9.Kf1, Black responds with 9...Qf5 and after 10.Qf3 Qxf3 11.gxf3 d5!? he is a bit better (better pawn structure, two Bishops, equally insecure Kings) even if White finds 12.h4!? to prevent ...Bh3+, forcing his King into the center where the enemy Rooks can roam.

By the way, Bill dispatched 7...Nxe4 quickly in a couple of games: Wall,B - NN, lichess.org, 2016 (1-0, 16) and Wall,B - TenAndOnly10, lichess.org, 2016 (1-0, 21)

8.Kxf2 Nxe4+ 9.Kg1 Rf8 



Preparing to castle-by-hand, a standard defensive plan in the Jerome Gambit; but overlooking the Queen check at d5 - odd, in that his Bishop sacrifice seemed aimed against that same eventuality.

Instead, 9...d5 would be about even, although Bill has a couple of wins against the move:  Wall,B - MyDrunkAccount, lichess.org, 2016 (1-0, 20) and Wall,B - Szachowski, playok.com, 2017 (1-0, 20). 

10.Qd5+ Ke8 11.Qxe4 Rf7 12.Nc3 d6 


This hurries Black's demise.

13.exd6+ Kf8 14.Qxh7 Qxd6 15.Qh8+ Ke7 16.Bg5+ Kd7 17.Rd1 Black resigned


Thursday, January 11, 2018

Jerome Gambit: Paths Off of Paths

The Jerome Gambit is an opening that is clearly "off the beaten path". Yet, in pursuing it, players often find themselves further afield - and it is good to know about some of those side paths as well.

It is clear in the following game that the defender was not prepared to have the game "Jerome-ized".

Wall, Bill - Guest761989
PlayChess.com, 2017

1.e4 e5 2.Nf3 Nc6 3.Bc4 Na5 4.Bxf7+ 



With his third move Black imagines a quiet win of the "minor exchange" with 4.Bb3 Nxb3. He is too hopeful, as White has, instead, 4.Nxe5, and after 4...Nxc4 5.Nxc4 d5 6.exd5 Qxd5 7.Ne3 White is a pawn up, and Black has little to show for it.

However, players familiar with the Jerome Gambit will be tempted to play the Bishop sacrifice on move 4, giving Black a very un-quiet game.

4...Kxf7 5.Nxe5+ Ke6 6.d4 d6



White has two pawns for his sacrificed piece, but his play against Black's King gives him adequate compensation.

7.Qg4+ Ke7 8.Qg5+ Ke8 



Better is 8...Nf6, although after 9.Nf3 Nc6 10.e5 dxe5 11.dxe5 Kf7 12.exf6 Qxf6 White would have a small advantage.

9.Qxd8+ 

It is important to note that in the 4 earlier games in The Database, White had tried 9.Qh5+. Best play would continue 9...g6 10.Nxg6 Nf6 11.Qh4 hxg6 12.Qxh8 Nxe4 When White would have a Rook and two pawns against a Bishop and a Knight. This is a small edge for White, and I can see why Bill chose a different path: His active Knights will go after the slumbering Rooks in the corners!

9...Kxd8 10.Nf7+ Ke8 11.Nxh8 g6 12.Nc3 Bg7 



As indicated.

13.Nd5 c6 14.Nc7+ Black resigned



Black will lose his other Rook, and while he will gather in the Knight at h8, he will have a very difficult time catching the other one, leaving him down a couple of exchanges, plus a pawn or two.

Tuesday, January 9, 2018

The Delayed Pie-in-the-Face

Image result for free clip art pie in the face

The difference between a very strong counter in the Jerome Gambit at move 6 and an ineffective defensive line (the same move one tempo later) shows the problem with delaying an active riposte. 

Wall, Bill - Guest6766281
PlayChess.com, 2017

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



4...Kxf7 5.Nxe5+ Nxe5 6.d4 Bb6



Black can decide which piece to save, the Bishop or the Knight. The text is a reasonable line.

Of course, Black's strongest response is to ignore both of the pieces and play 6...Qh4!?, what I have referred to as a pie-in-the-face variation.

7.dxe5 Qh4

A delayed pie-in-the-face? Tossing pies is very much a part of slapstick humor - and timing is always critical in comedy.

This line has been faced by Jerome Gambiteers chessmanjeff, frizerkaHR, GOH, HauntedKnight, jfhumphrey, ndrwgn, stretto, Wall and yorgos. As a group, they have not been impressed.

8.Qf3+ Ke7

A slightly better retreat is 8...Ke8, e.g. 9.Nc3 (9.O-O Ne7 10.Nc3 Rf8 11.Qe2 g5 12.Be3 Ng6 13.Nd5 Kd8 14.Qd2 h6 15.Bxb6 axb6 16.Nxc7 Kxc7 17.Qd6+ Kd8 18.Qxg6 Re8 19.Qxb6+ Ke7 20.Qf6 checkmate, Wall,B - Guest2616286, PlayChess.com, 2017) 9...Ne7 (9...Bxf2+ 10.Qxf2 Qxf2+ 11.Kxf2 Nh6 12.Nd5 Ng4+ 13.Kg3 Kd8 14.Bg5+ Nf6 15.exf6 h6 16.fxg7+ Ke8 17.gxh8=Q+ Kf7 18.Rhf1+ Kg6 19.Qxh6 checkmate, Wall,B - Shillam, lichess.org, 201610.g3 Qh3 11.Be3 d6 12.Bxb6 cxb6 13.exd6 Ng6 14.Nd5 Qd7 15.Nc7+ Kd8 16.Nxa8 Qxd6 17.Rd1 Ne5 18.Rxd6+ Ke7 19.Qc3 Kxd6 20.Qd4+ Ke6 21.Nc7+ Kf7 22.Qxe5 Rd8 23.Nb5 Bg4 24.Qf4+ Kg8 25.Qxg4 a6 26.Qe6+ Kh8 27.Nd6 Rb8 28.Nf7+ Kg8 29.Nh6+ Kh8 30.Qg8+ Rxg8 31.Nf7 checkmate, Wall,B - Itboss, lichess.org, 2016.

9.Nc3

Or 9.O-O Nh6 10.Nc3 Rf8 11.Nd5+ Kd8 12.Qxf8 checkmate, Wall,B - Guest2293428, PlayChess.com, 2017.

9...Nh6 10.Nd5+ Kd8

Once again, e8 is the better square for the King.

11.O-O

White also has the sneaky 11.h3!? threatening g2-g3, winning the Queen. Black could escape by returning a piece for two pawns, i.e. 11...Bxf2+ 12. Qxf2 Qxe4+ but White would be better.

For the record, 11.g3?! directly could be answered by 11...Qg4 and White does not gain much by exchanging Queens, while he would lose time if he movee his Queen to avoid the swap.

11...Bd4

Looking to grab the pawn at e5, but he is overlooking a few things. He could have maintained an even game with 11...c6 12.Nxb6 axb6.

12.g3 Qh3

Why was e8 the better square for Black's King to retreat to (as suggested in the note to move 10)?

Why was the Black Bishop's trip to d4 problematic (as mentioned in the note to move 11)?

Why couldn't Black retreat his Queen to g4 (as in the note to move 11), instead of h3?

13.Bg5+ Ke8 14.Nxc7 checkmate




Sunday, January 7, 2018

Jerome Gambit: Skeptical Defense

Wall, Bill - Guest673244
PlayChess.com, 2017

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



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



This is interesting. Bill usually plays 6.d4.

6...Ng6 7.Qd5+ Kf8 8.Qxc5+ d6 9.Qe3 Nf6 10.Nc3 Be6



Black develops a piece, and remains slightly better.

Despite the fact that his King is uncastled - and, therefore, he might feel more comfortable not opening up the  position - Black could have played 10...d5, and after 11.exd5 Kf7 12.0-0 Re8 13.Qd4 c6 he would have recovered his sacrificed pawn and his prospects would have been brighter than in the game.  

11.b3

Feeling adventurous, Bill bypasses the thematic 11.f4 and the reliable 11.d4 for a chance to put his Bishop on the long diagonal. We have seen this strategy for White before: why hurry? Let Black figure things out on his own.

11...Kf7 12.Bb2 Re8 13.O-O-O Kg8



Black has played steadily, developing his pieces and castling-by-hand.

This is just the kind of position that could feature opposite wing pawn storms, and White wastes no time in getting his started.

14.h4 Ng4

Black is not convinced. He could have tried 14...d5 or 14...h5 instead.

15.Qg3 Nf6 16.h5 Ne5



17.f4 Neg4 18.f5 Bf7 19.h6



This is what Bill is looking for: to open the h-file for his Rook, the g-file for his Queen, and the a1-h8 diagonal for his Bishop.

Black can stop White's plan, but he will have to give back some material.

19...gxh6

Instead, 19...d5 20.Rh4!? Qd6 21.Rxg4 Nxg4 22.Qxg4 Qxh6 23.Nxd5 would have helped on defense, although White would have two pawns for the exchange, and the initiative.

 20.Rxh6 Kf8 21.Qf4

21...Re5

Black remains skeptical, and it is easy to see why. Take, for example, his best defense, instead of the text: 21...Nxh6 22.Qxh6+
Ke7 His King appears to be escaping trouble, and he has an extra Rook (for two pawns). However, if White finds 23.Nb5!?, uncovering the Bishop, then after 23...Nh5 24.g4 Kd7 25.Qxh7 Re7 26.gxh5 he will have 3 pawns for the exchange - and the pawns will become more dangerous with each step forward.

22.d4 Re8

Come and get me, says Black.

23.e5

As you wish, says White.

23...Ng8

Tougher was 23...Qe7, when 24.Rxf6 Nxf6 25.Qh6+ Kg8 again leaves White a Rook down, but 26.Rh1 (better than 26.Rd3) Nh5 27.Ne4!? Qf8 28.Rxh5 Qxh6+ 29.Rxh6 again puts the first player in the better position, with two pawns for the exhange - and his pawns are ready to cause trouble.

24.Rxh7 Black resigned



I think Black was worn out and no longer skeptical. His Knight on g4 is hanging, his Bishop is threatened with e5-e6, and his King is not going to be able to escape, i.e. 24...Ke7 25.e6, etc.

Stockfish 8 gives as best 24...N4f6, when 25.exf6 Qxf6 26.Nb5!? would be too much for Black to deal with.