Some comments given by Mig during the live broadcast at Playchess.com are included.
1.e4
c5
2.Nf3
d6
3.d4
cxd4
4.Nxd4
Nf6
5.Nc3
a6
6.f3
e6
7.Be3
Nc6
8.Qd2
Be7
9.0-0-0
0-0
10.g4
Nxd4
11.Bxd4
b5
12.g5
Nd7
13.h4
Qc7
14.Kb1
b4
[ 14...Bb7
15.g6
fxg6
16.h5
Ne5
17.Bxe5
dxe5
18.Qd7
Bd8
19.Qxe6+
Qf7
20.Bh3
Bc8
21.Qxf7+
Kxf7
22.hxg6+
hxg6
23.Bxc8
Rxc8
24.Rd7+
Kg8
25.Rh3
Rc6
26.Nd5
g5
27.c3
g4
28.Rg3
Rh6
29.Rxg4
g6
30.Kc2
Kh8
31.Rd6
Kh7
32.Rd7+
Kh8
33.Kb3
a5
34.a4
b4
35.Kc4
bxc3
36.bxc3
g5
37.Rg3
Rh1
38.Kb5
Rg8
39.c4
Rb1+
40.Kc6
Rg6+
41.Rd6
Kg7
42.c5
Rc1
43.Rxg6+
Kxg6
44.Kd7
Rxc5
45.Kxd8
Rc4
46.Nb6
Rb4
1-0 Cioara,A-Efimov,I/Porto San Giorgio 2002/CBM 89 ext (46). ]
15.Na4
Bb7
16.b3
Bc6
17.Nb2
a5
18.h5
Ne5
19.Be2
a4
20.Nc4
Bb5
21.Nb6
Rab8
22.h6
Bxe2
23.Qxe2
g6
24.f4
Nc6
25.Nxa4
Nxd4
26.Rxd4
e5
27.Rc4
Qa5
28.f5
Bxg5
29.Rc6
Rfd8
30.Qg4
Be7
31.Rd1
Qa7
32.c3
Bf8
33.fxg6
hxg6
34.h7+
Kh8
35.cxb4
Rxb4
36.Qf3
Rdb8
37.Nc3
Qb7
38.Rcxd6?
Rxb3+!
39.Ka1
[ 39.axb3
Qxb3+
40.Kc1
Qb2#
]
39...Rxc3
[ 39...Rb2
]
40.Qf6+
Kxh7
41.Rb6
Spectacular, but the only move.
41...Qc7
42.Rh1+
Bh6
43.Rxb8
Rc1+
44.Rxc1
Qxc1+
45.Rb1
Qc3+
46.Rb2
Qe1+
47.Rb1
Qc3+
48.Rb2
Kg8
49.a4
Bc1
50.Qb6
I think this is a clear win now. The white king is just too open. His e-pawn gets picked off in many lines and black will still have two reserves!
Like most endgames, it's all a question of time. Since white has to lose a move to break the pin and move his king, there is no point in capturing on b2 yet.
50...Kg7
So Kasparov used his 'extra move' to get his king off the back rank and away from queen check and also safe from the white a-pawn queening with check.
"The more you look, the harder it is to find a concrete winning line for Kasparov. I'm sure he found that out himself long ago! Just pushing the pawn is not enough.
51.Ka2
[ 51.Qb4
Bxb2+
52.Qxb2
Qe1+
53.Qb1
Qd2
54.Qb5
Qc1+
55.Ka2
Qc2+
56.Ka3
Qxe4
57.a5
g5
58.a6
g4
59.Qb7
]
51...Bxb2
52.Qxb2
Qc4+
53.Ka3
Qxe4
54.a5
g5
55.Qd2
Watch one trick in these endgames. If Black plays his king to g6 and there is a pawn race, white queens the a-pawn, black queens the g-pawn, and Qg8+ wins the black queen.
This is either winning or it isn't. Computers need evals in order to decide what to play, so their move suggestions are interesting. BUT, it is not relevant to evaluating the position. There are many +3 positions that are dead draws (or theoretical wins) computers don't understand.
55...Qf4
56.Qd8
Now black catches up in "queening time" because if the white pawn goes to a7, Qe3+ puts it back in the box. So white will have to lose another move with his queen to protect the a-pawn.
56...Qc1+
Hmm, interesting choice by Kasparov. Not sure how the queen can be better on c1 than on f4. Too subtle for me. [ 56...g4!
57.a6
g3
58.a7
Qf3+
Now the queen covers the h5 square, so there is no perpetual check! 59.Kb4
g2-+
60.a8Q
Qxa8
61.Qxa8
g1Q-+
]
57.Kb4
Qb2+
58.Kc5
Qc3+
59.Kb5
So the queen gets back to the right diagonal with Qe3+ and THEN g4. I hope!
59...Qb3+
In his infinite wisdom, Garry decided e3 was better than f4 for the queen. From e3 it covers the critical a7 square.
60.Kc5
I'm still not sure if it really gains a tempo over the immediate 56...g4 line, but I'm willing to give him the benefit of the doubt! Mostly I think he wanted to make move 60 and get more time.
60...Qc3+
61.Kb5
Qb3+
62.Kc5
Qe3+
All those checks were exactly what the principles of endgame play tell you NOT to do! The white king was less active back on a3. But it shouldn't really matter in this line where the white king is.
63.Kb4
Qe4+
f3 was a key square for the black queen. It eliminated the perpetual. Now black doesn't have access to that square with check. From f3, the black queen covered the h5 square, so no perpetual. Now it looks like a draw.
64.Kc5
Qc2+
65.Kb5
Qe2+
66.Kb6
Qe3+
67.Kc6
g4
68.a6
g3
69.a7
g2
70.a8Q
Qe4+ Kc7 Qxa8 Qg5+ draw. And we should note that it's because of the active king on c7
70...Qe4+
71.Qd5??
[ 71.Kc7
Qc4+
72.Kb7
Qb3+
73.Kc6
Qc2+
74.Kb5
Qe2+
75.Kc6
Qe4+
76.Kc7
Qxa8
77.Qg5+
Kh7
78.Qh5+
Kg8
79.Qg5+
Kf8
80.Qh6+
Ke7
81.Qd6+
Thanks to the active white king, white has a perpetual check!]
71...Qc2+?
[ 71...Qxd5+
72.Kxd5
g1Q
73.Kxe5
A ChessBase program with tablebases will now happily inform you that this position is mate in 62! But that would almost certainly be harder for Black to win than the queen endgame with two black pawns. 73...Qg5+
74.Kd4
Qd2+
75.Kc5
Qe3+
76.Kb5
f5
77.Qd5
Kg6
78.Qg8+
Kh5
79.Qf7+
Kg4
80.Qg6+
Qg5
81.Qe6
Qf4
82.Kb6
Kg3
83.Qb3+
Qf3
84.Qg8+
Kf2
85.Qh8
f4
86.Kc7
Qe3
87.Qb2+
Kf3
88.Kb8
Qe8+
89.Kb7
Qe7+
90.Ka8
Qf8+
91.Kb7
Kg3
92.Qd4
Qe7+
93.Ka8
Qa3+
94.Kb7
f3
95.Qg1+
Kf4
96.Qd4+
Kf5
97.Qd5+
Kg4
98.Qd4+
Kh3
99.Qh8+
Kg2
100.Qg8+
Kf1
101.Qc4+
Ke1
102.Qe4+
Kd2
103.Qd4+
Kc2
104.Qb6
Kc1
105.Qg1+
Kb2
106.Qg3
Ka2
107.Qf4
Ka1
108.Kc6
Qd3
109.Qc1+
Ka2
110.Qc5
Kb2
111.Qb4+
Qb3
112.Qh4
Qc2+
113.Kd7
f2
114.Qd4+
Kb1
115.Qb4+
Kc1
116.Qa3+
Qb2
117.Qa6
Qd2+
118.Ke7
Qe1+
119.Kd6
f1Q
120.Qa1+
Kc2
121.Qa2+
Kc3
122.Qa3+
Kc4
123.Qc5+
Kb3
124.Qd5+
Qc4
125.Qb7+
Kc3
126.Qf3+
Qd3+
127.Qxd3+
Kxd3
128.Kc6
Kc4
129.Kc7
Qe6
130.Kb8
Qd7
131.Ka8
Kb5
132.Kb8
Ka6
133.Ka8
Qe8#
Yep, that's 62!]
72.Kd6
Qg6+
73.Kc7
g1Q
74.Qxe5+
Qf6
[ 74...f6
This move offered the last of the winning chances, although very difficult to prosecute. Both players were down to their last minutes.]
75.Qh8+
Kxh8
76.Qxf6+
Qg7
77.Qh4+
Kg8
78.Kd6
Qg6+
79.Ke5
Kg7
80.Qe7
Dead draw now.
80...Qg3+
81.Kf5
Qg6+
82.Ke5
Qh6
83.Kf5
Qg6+
84.Ke5
Kh7
85.Qh4+
Kg8
86.Qd8+
Kg7
87.Qe7
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