Clearly, that it is necessary to move by wR. However to find a correct square for the rook not so simple.
1.Rc8!!
[1.Rc4+?
Kg3!
2.Bxe3
Sh3
3.Rc2
Bf6
now, White has not good move and will lost wB for Pg2. If White will try to use the move - Rc1, than will be Bg5 with draw. 4.Rc1
Bg5
5.Bxg5
Sxg5=
; 1.Rc7?
e2
(1...Se2?
2.Bxe3
g1Q
3.Bxg1
Sxg1
4.a4
Be5
5.Rd7
Bg3
6.Rh7+
Kg4
7.Rg7+
Kh4
8.Rxg3
Kxg3
9.a5+-
) 2.Kd2
and the play same as in main line (2.Re7
Sh3!
(play for the fork in ase of 3.Rxe2) 3.Kxe2
g1Q
4.Bxg1
Sxg1+=
) 2...Sh3
(esli - 2...e1Q+
situation as in line1.Rc6?) 3.Kxe1
Sf3+
4.Ke2
g1Q
5.Bxg1
Sxg1+
6.Ke3
Ba3
7.Kf2
Sh3+=
) 3.Kxe2
g1Q
4.Bxg1
Sxg1+
5.Kd2
Sf3+
6.Ke3
Be5!
this move save the Black because wR on c7 and wB has good move (6...Kg4?
7.Rc4+
Kg3
8.a4
and play leads to main line) 7.Rc4+
Kg3
8.a4
Bb8
9.a5
Ba7+
10.Ke4
(10.Ke2
Se5=
; 10.Kd3
Se5+=
) 10...Sd2+=
; 1.Rc6?
e2
2.Kd2
e1Q+
3.Kxe1
Sf3+
4.Ke2
g1Q
5.Bxg1
Sxg1+=
] 1...e2
[1...Sh3
2.Bxe3
Kg3
(2...Bf6
3.a4
Bg5
4.Rg8
Kg4
5.a5
+-) 3.a4
Sf2+
4.Ke2
g1S+
5.Kf1
Se4
6.a5
Sh3
7.a6
and wins] 2.Kd2! [Thematic try 2.Re8!?
Sh3!
(2...Sf3?
3.Rxe2
Ba3
4.Re8
Kg4
5.Rg8+
and the Black has not chance for a draw) 3.Kxe2
g1Q
4.Bxg1
Sxg1+
5.Kd3
Sf3!
(5...Ba3?
6.Kc4!
Sf3
7.Re3
Sd2+!
8.Kb5!
Bb2
9.a4+-
) 6.a4
Se5+!
7.Ke4
Sd7!
(7...Sc4?
8.Rb8!
Bc3
(8...Bf6
9.Rb4!+-
) 9.Kd3!+-
(9.Rc8?
Sd6+=
) ) 8.Re7
(Rd8) 8...Sc5+=
] 2...Sh3!
[2...e1Q+
3.Kxe1
Sf3+
4.Ke2!
Sd4+
5.Kf2
Se6
6.Kxg2+-
] 3.Kxe2
[3.Rc4+?
Kg3
(Kg5)= (3...Kh5?
4.Kxe2
g1Q
5.Bxg1
Sxg1+
6.Ke3!!
Ba3
7.Rc3
Bb4
8.Rb3
Bc5+
9.Ke4
Se2
10.a4+-
) ] 3...g1Q
[3...Kg3
4.Bc7+
Kh4
5.Bh2
Sg5
6.Bg1
Sh3
7.Bf2+
Kg4
8.Rg8+
Kf5
9.a4+-
] 4.Bxg1
Sxg1+
5.Kd2!
Ba3
[main 5...Sf3+
6.Ke3
(if was the move 1.Rc7? now will save the Black ...Be5! ) 6...Kg4
7.Rc4+
Kg3
8.a4
Be5
9.a5
and win (EGTB); 5...Kg3
6.a4!
Kf4
7.Kd3
Sf3
8.Rf8++-
] 6.Kd1!!
zz [6.Kc2?
Se2!
7.Kb3
Bc1
8.a4
Bd2
9.Rc2
(9.Rd8
Ba5=
) ...Sd4+=
] 6...Sh3
[also 6...Kg4
7.Rg8++-
; also 6...Sf3
7.Rc3+-
; also 6...Kg3
7.Rc3++-
; also 6...Bd6
7.a4
Bb4
8.Rc4++-
] 7.Rc4+
Kh5
8.Rc3+-