1.e4
This matchup took place in the New York Masters, which is an action chess event in New York City. What's remarkable about this game is that Jenn usually fares better in slower time controls, as she has some time trouble weaknesses.
1...c5
2.Nf3
e6
3.d4
cxd4
4.Nxd4
Nf6
5.Nc3
d6
6.Be2
It was surprising to see Jenn avoid the Keres attack with 6.g4, as such aggressive play usually suits her style. 6.Be2 is a much more restrained move and one would think that playing it would favor the more experienced Grandmaster. Jenn still manages to drum up a nice attack, without using the caveman style approach of 6.g4
6...Be7
7.0-0
a6
8.Kh1
Although this may seem like a waste of time, this move is often very useful in the Sicilian. It usually makes sense to get it out of the way now, before many variations occur where black can save himself with pins and checks along the a7-g1 diagonal.
As minute as this sounds, moves like Kh1 are one of many reasons why endgames often favor black in the Sicilian. The king on h1 is usually much further from the action than her black counterpart. However in the middlegame, the king is happy on h1.
8...Qc7
9.a4
A very typical move in such Schevinegin Sicilian structures. a4 stops black from expanding with ...b5, and also prepares a later a5 herself.
The only downside of this move is weakening the b4 square, however this usually isn't a serious factor.
9...b6
10.f4
Bb7
11.Bf3
Bf3 is the most typical placement for white in such positions. Bd3 is also an option, preparing to use the bishop to attack the kingside later on, after an eventual e5 push by white.
11...Nc6
12.Nxc6
Bxc6
13.Qe1
Qe1 is usually more precise than Qe2, as the queen not only prepares e5, but also can swing over to the kingside via g3 or h4.
13...0-0
14.b3!
White prepares to actively develop the only piece that's not involved in the game. The instinctual move 14.Be3 is less precise, as the bishop has no real plan on the g1-a7 diagonal. On b2, the bishop will take a great part in a later kingside attack. If you can get away with it, it's often better to develop one move slower, if it'll allow you to place a piece on a stronger square.
14...b5
15.Bb2
b4
16.Nd1
e5
A risky decision by Ehlvest, sacraficing a pawn.
17.Qxb4
exf4
[17...d5
18.Bxe5
Bxb4
19.Bxc7
dxe4
White has a safe extra pawn. It's obvious why Ehlvest would want to avoid a pawn down endgame against a player rated 300 points less than him. 20.Be2
]
18.Qc3
Pinning the f6 knight to the g7 pawn. White has a clear advantage here, as the bishop and queen battery along the a1-h8 diagonal is extremely powerful. [18.Qd4
This move may have been more accurate than Qc3. It's more centrally placed, and if black puts a rook on the c-file , the white queen doesn't have to move again.]
18...Qb7
19.Nf2
A convenient move that defends the e4 pawn, but also develops a knight that was doing nothing on d1.
19...Rac8
20.Qd4
Rfd8
21.Rae1
White is slowly building up, and black has no real counterplay.
21...Ne8
Preparing ....Bf6. Its time for white to take some action, before black untangles himself..
22.Ng4!
It seems as though this move fails, because black can kick the knight away with ...h5 and then play ...Bf6 as planned.
22...h5
23.Nh6+!
This move was easy to see, however it wasn't so clear what white shuold do if black were to simply move the king, retaining the idea of ....Bf6
23...Kf8
24.Nxf7!
This the kind of sacrafice that you would probably have to pay Jenn Shahade not to play. When she smells blood she can be relentless, as the 2 time World Championship Candidate Jan Ehlvest will soon find out.
24...Bf6?
When facing such aggressive play, even if it may not be objectively decisive, it can be very tough to find strong defensive moves under pressure. This is especially true in action chess time controls, as attacking moves are usually more instinctive than defensive moves. [24...Kxf7
This is by far the most testing variation, however Jan made an oversight in the game variation, that convinced him to choose that path. 25.Bxh5+
Kg8
26.Bxe8
Eliminating the defender of g7, however this strangely may not be white's best move. (26.Rxf4
Bf6
27.Qf2
Rc7
28.Bg6
) 26...Bf6
Blacks only move, but suddenly things are not so clear. White will have to sacrafice either a piece or the exchange. In both cases white will have more than ample compensation in the form of pawns, but the game becomes quite unclear. 27.Bxc6
(27.Qc4+
d5
28.Bxc6
Rxc6
29.Qe2
Bxb2
30.exd5
Rf6~~
) 27...Qxc6
28.e5
Bxe5
29.Rxe5
dxe5
30.Qxe5
Qg6~~
]
25.e5!
[25.Nxd8
This simple move is also decisive. 25...Bxd4
26.Nxb7
Bxb2
27.Na5
Bc3
28.Nxc6
Bxe1
29.Nd4
Bc3
30.Ne6+
Ke7
31.Nxf4
]
25...dxe5
This was not Ehlvests best defensive chance, as he now loses immediately. [25...Qxf7
26.exf6
Nxf6
27.Qxf4+-
This was relatively stronger, but still totally winning for white.]
26.Nxd8
Bxd8
27.Qxe5
Bf6
28.Ba3+
Kf7
29.Qe6+
Kg6
30.Bxc6
Winning the knight on e8, and forcing resignation [30.Bxc6
Qxc6
31.Qxc6
Rxc6
32.Rxe8+-
] 1-0