Jerome Gambit for Dummies 2.0 (Part 3)

                                            

[continued from the previous post]

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

It is worth starting off with a quote from the post"The Spectre of the Jerome Gambit (Part 1)"

For most club players, it is easier to attack than defend; and that works in the Jerome Gambit's favor, as its whole idea is attack. 

The essence of a gambit is that White (in this case) gives up material for something. We refer to the Jerome Gambit, not the Jerome Blunder (although some might prefer that name, and the editor of the American Chess Journal referred to it in 1877 as "Jerome's Absurdity"). The defender struggles to make sense out of an opening that isn't familiar - but White wouldn't sacrifice pieces for nothing, would he? 

Also, most club players have been exposed to "Checkmate in X moves" problems, but they have rarely faced "Black to move and escape the mating net" challenges. They learn how to attack, but they also learn that a King out in the open is one that will perish. 

So, being attacked can be unsettling, and for a club player it may very well lead to a distracted or diminished mental state. 

All of which addresses the point that sometimes the Jerome Gambit wins when it "objectively" shouldn't. 

Although 98% of the time (according to The Database) Black captures the Bishop, the move is not forced. It is simply a choice for the second player between having an "objectively" winning game with 4...Kxf7 and having the worse position after 4...Kf8 or 4...Ke7.

Jerome Gambit Declined

Jerome Gambit Declined

Yet a few defenders will adopt the sly attitude If he wants me to take the Bishop, then I won't take it.

There is some "psychology" in this, too: the Jerome Gambiteer suddenly finds himself "stuck" with a calm, but "objectively" better game than had been expected a move before. This change of fortune can take some getting used to.

For this reason, even though it is an unlikely event, for peace of mind White might want to prepare a response to the Jerome Gambit Declined.

In the first place, White can feel reassured when facing the Gambit Declined. The Database has 471 games with 4...Kf8 with White scoring 61%; and 59 games with 4...Ke7 with White scoring 70%. Stockfish 14.1 (30 ply) rates White about 3 pawns better in the first case, and about 4 pawns better in the second.

White can respond to the Jerome Gambit Declined with the simple 5.Bb3, knowing that he has invested a couple of tempos to obtain a pawn and prevent Black from castling. (Also possible are 5.Bc4 and 5.Bd5.) The Database shows White with 5.Bb3 scoring 66% against 4...Kf8 and 100% against 4...Ke7.

White can part with his Bishop, instead, with 5.Bxg8, scoring 63% against 4...Kf8 and 91% against 4...Ke7. (Personally, I like to keep the Bishop.)

Some players seeking greater complications have left the Bishop in place and tried 5.Nxe5, apparently hoping to continue along orthodox Jerome Gambit lines, gaining a tempo when Black finally plays ...Kxf7. White has been successful with 5.Nxe5 over-the-board (The Database has 68 games, White scores 60%) even though the computer frowns upon the move, seeing Black about 1 3/4 pawns better. (It must be noted that the tries 4...Kf8/4...Ke7 5.Nxe5 Nxe5 6.Qh5 d6 and 4...Kf8/4...Ke7 5.Nxe5 Nxe5 6.d4 Nxf7 are not very encouraging for White.)

Of course, there is also the rare 5.Qe2 with the idea of Qc4+ to then capture the enemy Bishop at c5, and 5.b4, to transpose to a sort of Evans Jerome Gambit declined. Although each line leads to an advantage for White, it is not necessary to be this creative.

4...Kxf7

Jerome Gambit Accepted

We finally arrive at the second Critical Position.

The "classical" Jerome Gambit continues with 5.Nxe5 (about 60% of the games in my database that start 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ Kxf7) while "modern" Jerome Gambits (not played by Jerome and his contemporaries, mostly internet games) continue with alternatives such as 5.Nc3, 5.d3, or 5.0-0. 

Thirteen years ago, in "Jerome Gambit for Dummies (2)" I wrote

For the record, after a very long think (over 12 hours) Deep Rybka 3.0 Aquarium assesses Black as being 1.91 pawns better after 5.Nxe5+ as well as after 5.Nc3. It sees White being only 1.72 pawns worse after 5.d3 or 5.0-0.

One fifth of a pawn doesn't seem like a lot to me, and I still prefer the complications of 5.Nxe5+. Jerome Gambiteers who feel they can knuckle down and simply outplay their opponents with the "modern" variations are free to disagree with me.

Computer chess engines have improved mightily since 2009, and now Stockfish 14.1 (30 ply) rates 5.Nxe5+ as a little more than 4 pawns better for Black, as opposed to 5.Nc3 (about 5 3/4 pawns better for Black) 5.d3 (a bit more than 6 pawns better for Black) and 5.0-0 (about 4 3/4 pawns better for Black).

So, today the computer says Play 5.Nxe5+, but If you don't want to sacrifice a second piece, play 5.0-0.

[to be continued]

Jerome Gambit for Dummies 2.0 (Part 2)

                               

[continued from the previous post]

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

The Jerome Gambit

This is the first Critical Position in what is generally referred to as the Jerome Gambit. (There are variations, which will be noted below.)

The Database has 22,156 games with this position. White scores 50%. This number has been creeping upwards over the years. 

Looking back, 12 years ago, according to "Opening Reports on the New Year's Database", this position scored 44% for White.

Improving, 4 years ago, according to "The Database Upgrade", this position scored 46%.

Why the increase?

There is always the possibility of "sampling bias" - that Readers of this blog send me their wins, but not their losses, so that success is over-represented. Likewise, that published wins uncovered by my research are more likely than published loses.

I have worked to overcome this bias by including all 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ games (wins, losses and draws) from the FICS database, from 1991 through November 2021, to give a representative (i.e. of online club play) selection. To be fair, over time the portion of The Database that is FICS-derived has dropped from about 95% (see "What Exactly is 'The Database' ?") to a current 56% - primarily due to an influx of games from lichess.org (Thank you, Dan Middlemiss!) although, again, they seem balanced between wins, losses and draws.

It is also possible that Jerome Gambit players, over time, have gotten better, and that is reflected in the improved scoring. Or it could be that increased interest has attracted stronger players, who, in turn, have been more successful with the Jerome.

Before moving on, I want to make a couple of comparisons. If you look at the Italian Four Knights Jerome Gambit - 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4.Nc3 Bc5 5.Bxf7+

Italian Four Knights Jerome Gambit

The Database has 2,969 games with this position, with White scoring only 39%. This is comparable to 38%, 4 years ago. This difference in results from the main line Jerome Gambit (39% vs 50%) occurs even though Stockfish 14.1 sees Black's position in the Italian Four Knights Jerome Gambit as only a little more than a half-pawn better (at 30 ply depth) than in the regular Jerome Gambit.

Perhaps this is why, of late, I have been seeing more Jerome-like Bishop sacrifices against the Two Knights Defense, i.e. 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4.Bxf7+, not waiting for the Italian Four Knights Jerome Gambit to develop. The Database is not representative, here, but notably has 735 game examples, with White scoring 46%.

Clearly, I need to do more resarch on the Italian Four Knights Jerome Gambit.

Finally, The Database has 447 Semi-Italian Jerome Gambit games, 1.e4 e5 2.Nf3 Nc6 3.Bc4 h6 4.Nc3/0-0 Bc5 5.Bxf7+. 

Semi-Italian Jerome Gambit

Semi-Italian Jerome Gambit

 White scores 51% with 4.Nc3, and 62% with 4.0-0. That is a significant difference, even though Stockfish 14.1 (at 30 ply) sees 4.0-0 as less than a 1/2 pawn better.

(It is likely coincidental that in the two examples given, above, an increase of 1/2 pawn in Stockfish's evaluation is accompanied by a roughly 10% in scoring results.)

[to be continued]

Jerome Gambit for Dummies 2.0 (Part 1)

 

Five and a half years ago, in the post "More About The Jerome Gambit" I reminded readers of this blog

Visit the library or bookstore and you will find many helpful introductory books in the "...For Dummies" series. They are very popular. 

So - why not a "Jerome Gambit for Dummies" book? 

That was my inspiration for a series of posts - "Jerome Gambit for Dummies" 1, 2, 3, 4 and 5. 

These posts included a series of "Critical Positions" that develop as the Jerome Gambit (1.e4 e5 2.Nf3 Nc6 3.Bc4Bc5 4.Bxf7+) is played. They are good instruction for those new to the Jerome, and review for more experienced players.

There is also some research worth reviewing.

"More About The Jerome Gambit" continued

Later I offered "The Return of Jerome Gambit for Dummies" 1, 2, 3, 4, 5, 6, 7 and 8.

This series of posts "builds" the Jerome Gambit from the shortest game in The Database (you may be surprised how short), move-by-move, to the opening you are familiar with.  

Since the original Jerome Gambit for Dummies series began in 2009, and the second series began in 2012, I thought it was time to upgrade. Hence "2.0". I will include newer information, drawn from The Database, guided by the insights of Stockfish 14.1 and Komodo 12.1.1, and directed by my own developing experience - have I learned anything over the intervening decade? - and that of other Jerome Gambiteers.

[to be continued]

Blackmar - Jerome Gambit Revealed

 

I have been puzzled by Karel Traxler's reference to the "Blackmar - Jerome Gambit" (see " 'Tis A Puzzlement..." and "The Blackmar - Jerome Gambit?!").

Yury V. Bukayev's suggestion is very interesting. Here it is. 

Here is my version about Mr. Traxler's name 'Blackmar-Jerome gambit'.

Mr. Traxler's publication with this strange name was published in the October 11, 1892. My version is based on that he has read Mr. Gossip's text of 'The Chess Player's Vade Mecum' (1891):

> " We have therefore eliminated obsolete openings and confined
> ourselves merely to a brief examination of a dozen of the leading
> debuts...; omitting those openings in which the defense is declared by
> the most competent theorists to be weak or inferior, as for example
> Philidor's and Petroff's Defenses to the Kings Knight's opening; the
> Sicilian; the Greco Counter Gambit; Center Counter Gambit;
> Fianchettoes, Blackwar and Jerome Gambit, etc. ".

Please, look attentively at the part of this text:
" Philidor's and Petroff's Defenses to the Kings Knight's opening; the
Sicilian; the Greco Counter Gambit; Center Counter Gambit;
Fianchettoes, Blackwar and Jerome Gambit, etc. ".

> I think, Mr. Traxler asked himself: "Is there Blackwar Gambit in chess?" And he answered himself: "I don't know it. I know Jerome Gambit, I don't know Blackwar Gambit. It maybe, Mr. Gossip has written about Blackmar Gambit here, but I'm not sure". Then he said to himself: "The variant of an interpretation of this text "Blackwar & Jerome Gambit" ( = "Blackwar-Jerome Gambit") is very possible too! It maybe, Mr. Gossip knows much more than I about who is the first creator/player of 4.Bxf7+ in Giuoco Piano, so it maybe he has said here that Alonzo Jerome wasn't the first one! Thus, here is my main question: are here in this text two gambits - Blackwar (or Blackmar?!) Gambit and Jerome Gambit - or this one (BJG) only? I should analyse the language structure of Mr. Gossip's sentence to find a right answer". And Mr. Traxler started to do it. He said to himself: "Mr. Gossip has written:
> "Blackwar and Jerome Gambit"
> (not "Blackwar and Jerome Gambits"), although he has written in the same sentence:
> "Philidor's and Petroff's Defenses" ,
> so it is extremely notable!" Then Mr. Traxler said to himself: "Moreover, Mr. Gossip has written:
> "the Greco Counter Gambit; Center Counter Gambit;"
> (not "the Greco and Center Counter Gambits"), so it is notable that he hasn't grouped names of two these (counter) gambits in this sentence as "... and ... Gambits": probably, each counter gambit and each gambit isn't grouped as "... and ... Gambits" in this sentence". Then Mr. Traxler said to himself: "In result, I think that Mr. Gossip has written about one gambit, not about two ones, probably". Finally, Mr. Traxler asked himself in 1892: "Will it be good to publish " Blackwar ", if it is " Blackmar ", in fact? It will not be good for the newspaper and for me!"

That is why he has published the name "Blackmar-Jerome", I think.

Jerome Gambit: The Hurrieder I Go, The Behinder I Get

It takes skill - and quick reflexes - to be successful in a 1-minute bullet game. The following contest shows the defender coming up with an interesting move that should have caused his opponent to use up precious seconds of thinking time. Perhaps it did, but Black also produced a couple of moves that undid much of his own hard work.

The Jerome Gambit (1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+) can be like that. Doubly so in bullet.  

chessjuan1972 - relja01

1 0 bullet, lichess.org, 2022

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 

4...Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Ke6 7.f4 Nd3+

As I pointed out in "Brilliant, but Not Sound"

Ahhh... The joys of being two pieces ahead! There are so many ways for Black to return material.

Jerome Gambiteers should pay attention, as this admittedly unpopular move, nonetheless, leaves Black better.

8.cxd3 Qf6  

Black quickly puts his Queen on a square where she often is effective against the Jerome. Unfortunately, this leaves the Bishop hanging. A move that opened up lines and interrupted the attack on the piece was 8...d5.

9.Qd5+ Ke7 10.Qxc5+ d6

White is up a couple of pawns, but that is not usually the deciding factor in such a quick game.

11.Qe3 

Computers that think faster than a speeding bullet suggest that 11.Qxc7+ was playable and even better than the text move - but, seriously, this is a human vs human game.

11...Bd7 12.O-O Nh6 

13.Nc3 Ng4 14.Qg3 Rhf8 

The last slip.

15.Nd5+ Black resigned

Ouch.

 

Jerome Gambit: For A Moment Not So Annoying

In the following game, White faces a Jerome Gambit defense that can cause its share of headaches. However,  a couple of minor slips by Black suddenly change the game into a miniature. 

Fegatello25 - Thedarkripper

5 0 blitz, lichess.org, 2022

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 

4...Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Ke6 7.f4 d6 

As I mentioned in "Jerome Gambit Secrets #6"

I have called this the "annoying defense" (because it is) or the "silicon defense" (because of the affinity computer chess programs have for it). It was first seen in D'Aumiller - A.P., 1878 and figured in six of Alonzo Wheeler Jerome's games against S.A. Charles in their unfinished 1881 correspondence match.

Years ago, in "An International Master Refutes the Jerome Gambit".International Master Gary Lane, in his The Greatest Ever Chess Tricks and Traps (Everyman Chess, 2008) says

I think this is the best way to defend: allowing one of the extra pieces to be taken, and in return obtaining a solid position with extra material.

The fact that Black's King can hang around in the center in apparent safety - is annoying.

8.fxe5 dxe5 9.Qh3+ Kd6 10.Qd3+ Ke7 11.Qg3 

White's Queen and Black's King engage in a seemingly meaningless dance that reinforces the notion that the defender's monarch is completely safe.

With only one pawn in exchange for his sacrificed piece, White arrives at the above position with the opportunity to grab either the e-pawn or the g-pawn.

According to The Database, there are 60 previous games that reached this point, with 26 wins, 23 loses, and 11 draws for White - a decent 53%. Stockfish 14.1 (31 ply), however, sees Black as more than a Rook better. 

I would love to add encouragement from my personal experience, but the one time I arrived at this position was a prelude to disaster - see "Jerome Gambit: Back to the Drawing Board".

11...Bd6  

Black protects his e-pawn. Remarkably, the computer suggests that instead of this novelty he should ignore both en prise pawns and play 11...Ke8 with advantage.

12.Qxg7+ Ke6 

Well-played for a blitz game. True, Black's King might be safer after 12...Ke8, but his Rook at h8 would not be.

13.O-O 

Taking advantage of the fact that Black's repositioned Bishop allows castling, White adds his Rook to the attack on the King.

13...Ne7 

The proper place for the Knight is on f6, and although the game remains complex, White is probably a bit better. An odd line explored by Stockfish 14.1 and Komodo 12.1.1 is 13...Nf6 14.d4 exd4 15.Bg5 Be5 16.Rf5 Rg8 17.Rxe5+ Kxe5 18.Bxf6+ Ke6 19.Qxh7 Kxf6 and both computers say the game will be drawn by repetition of position

analysis diagram

Instead, White now has a forced checkmate.

14.Qg4+ Nf5 15.Qxf5+ Ke7 16.Qf7 checkmate

Jerome Gambit: Still Relatively Obscure

On page 48 of Ten Ways to Succeed in the Opening (2001), by Timothy Peter Talbut Onions and David Regis, you will see a diagram familiar to many of those who play the Jerome Gambit.

The authors write

Here, White has attacked straight from the opening, and has won a Rook and two Pawns for a Bishop. 

But look at the pieces left! Black's pieces can all come into the attack quickly, while White's are sitting around the edge. 

Black is winning here: try it!

It is clear that the authors were impressed by the finish to the Jerome Gambit game Amateur - Blackburne, London, 1884 - the collection Mr. Blackburne's Games at Chess (1899) dated the game at "about 1880" but contemporary accounts give 1884 - which continued from the diagram: 8...Qh4 9.O-O Nf6 10.c3 Ng4 11.h3 Bxf2+ 12.Kh1 Bf5 13.Qxa8 Qxh3+ 14.gxh3 Bxe4 checkmate

Amateur - Blackburne, London, 1884

It is worth pointing out, however, that, contrary to Onions' and Regis' assessment, Black is not winning in the first diagram. Instead, White has two lines of play that lead to better positions after 8...Qh4, Black's strongest move.

9.O-O Nf6 10.Qd8 Bb6 11.e5 dxe5 12.Qd3; and

9.d4 Nf6* 10.Nd2 Bxd4 11.0-0 Ng4 12.Nf3 Qxf2+ 13.Rxf2 Bxh8 14.Rf1 

To be fair, the Jerome Gambit is still a relatively obscure opening, and was even moreso, 20 years ago. Quite likely the Blackburne game was the only one the authors were familiar with.  

(* There is a wild and wonderful alternative, here, producing scary chess for White, but which is objectively even worse for Black than the main line: 9...Bb4+ 10.c3 Bh3 11.gxh4 Qxe4+ 12.Kd2 Qh4 realizing that taking the Rook allows White's Queen to escape and harass his King with Qxh7+ 13.cxb4 Re8 14.Kc2 Ne7 15.Qxe8+ Kxe8 16.Nc3 Qxf2+ 17.Bd2 Qf5+ 18.Kb3 and White has 2 Rooks and a Bishop for his Queen)