1.Kg1!
[1.Re2+?
Kd3
2.Re3+
Kc4
3.Rxh3
b2-+
] 1...Bf3!
[1...Bc3
2.Be1!
b2
3.Re2+
Kd3
4.Rxb2
Bxb2
5.Kh2
Bc8
6.Bxh4=
; 1...b2
2.Re2+=
] 2.b7!
[2.Kh2
b2
] 2...Bxb7
3.Kh2!
[3.Re2+?
Kd3!
4.Re3+
Kc4
5.Kh2
b2-+
] 3...Bg2
4.Re2+!
Kd1
[main 4...Kd3
5.Re3+!
Kc4
6.Rxb3!
Kxb3
(6...Be5+
7.Bg3
hxg3+
8.Rxg3=
) 7.g7!
Bxg7
8.Bd4!
Bf8
9.Bc5!
Bh6
10.Be3
Bxe3
Stalemate - Bosshard's idea] 5.Re8!
[5.Re1+?
Kd2
6.Bxh4
b2
7.Bg3
Bg7
8.Rg1
Kc2-+
] 5...b2
[main 5...Bc3
6.Bd4!
Bxd4
(6...b2
7.Bxc3
b1Q
8.Re1+=
) 7.Rd8
b2
8.Rxd4+
Kc2
9.Rb4
(c4)=] 6.Rxh8
b1Q
7.g7
Bd5!
[7...Ke2
White draws sooner 8.Be1!!
Bd5
9.g8Q
Bxg8
10.Rxg8
Qe4
main line] 8.g8Q
Bxg8
9.Rxg8
Ke2
[9...Qe4
(c2) 10.Rg1+=
] 10.Be1!!
[10.Bxh4?
Qe4!-+
] 10...Qe4
[10...Kxe1
11.Rg1++-
; 10...Qxe1
11.Re8+=
] 11.Rg1
Qd4
12.Rh1
Kf3
13.Rg1!
[13.Rf1+?
Kg4
14.Rg1+
Kh5-+
] 13...Ke2
14.Rh1
positional draw.