Analysis by Fritz.
1.e4
c5
2.Nf3
d6
3.Bb5+
Bd7
4.Bxd7+
Qxd7
5.0-0
Nc6
6.c3
Nf6
7.d4
cxd4
[This pawn sacrifice was first offered by Ervin Haag in 1959. White gets adequate compensation if Black plays 7...Nxe4
]
8.cxd4
Nxe4?
But capturing now is definitely bad for Black. In the ChessBase database White scores 76% from this position.
9.d5
Nd8?
[The only acceptable move for Black is 9...Ne5!
when White regains the pawn with the initiative after 10.Nxe5
dxe5
11.Re1
Nf6
12.Rxe5
]
10.Re1
Nf6
11.Bg5
Black's predicament is becoming clear. How can he complete his development?
11...h6
[The natural 11...g6??
fails miserably to 12.Bxf6
; while 11...e6
12.Bxf6
gxf6
13.Nc3
Bg7
14.Nd4
0-0
15.Qh5
f5
16.Rad1
is very pleasant for White]
12.Bxf6
gxf6
13.Nc3
Rg8
14.Ne4
The white knights head for the weak white squares.
14...Bg7
15.Nh4
Kf8
16.Qh5
[16.Ng3
e6
17.dxe6
Nxe6
18.Nhf5
Rd8
19.Qh5
is more accurate. Either way, Black is tied up in knots.]
16...Rc8
17.Nf5
Rc7
18.Re3
Qb5
19.Rae1
[19.Nexd6!
is devastating: 19...exd6
20.Nxd6
Qd7
21.Rae1
]
19...Qxb2
[19...Qxd5
also fails: 20.Nexd6
Qd2
21.Nxe7
Qxd6
22.Nxg8
Kxg8
23.Re8+
Bf8
24.Rd1
Qc5
25.Qxc5
Rxc5
26.Rexd8
and White wins]
20.Nexd6
e5
[20...exd6
is obviously impossible: 21.Re8#
]
21.Nxg7
[Had I been half awake I'd have played 21.dxe6
, winning very easily: 21...Nxe6
(21...fxe6
22.Qe8#
; 21...Re7
22.Nxe7
Kxe7
23.exf7+
) 22.Rxe6
with mate to follow. Instead, I just played the winning line that I'd already calculated.]
21...Rxg7
22.Qxh6
a6?
23.Nf5
Rc1
24.Nxg7
[24.Qh8+
Rg8
25.Qxf6
Nc6
26.dxc6
is a quick way to mate. In any case, Black could resign now.]
24...Rxe1+
25.Rxe1
Ke7
26.Nf5+
Kd7
27.Qc1
Qxa2?
28.Qc5
Qa4
29.Qd6+
Kc8
30.Ne7#
1-0