Karsten Müller analyses this position as win for black.
8/R4p2/6p1/4k2p/p6P/r5P1/5PK1/8 b - - 0 44
He thinks 44.. Kd5! is the only move to win. I tried to follow his suggestions whilst playing against Shredder to no avail.
1...Kd5 2.Kf1 Kc5 3.Ke2 Ra2+ 4.Kf3 f5 5.Ke3 Kb4 6.Rb7+ Kc3 7.Rc7+ Kb3 8.Rb7+ Kc2 9.Rc7+ Kd1 10.Rd7+ Ke1 11.f3 Rb2 12.Kf4 a3 13.Ra7 Rb3 14.g4 Rb4+ 15.Kg5 hxg4 16.Rxa3 g3 17.Ra2 Kf1 18.Kxg6
8/8/6K1/5p2/1r5P/5Pp1/R7/5k2 b - - 0 18
18..g2 19.Kxf5 g1=Q 20.Ra1+ Kg2 21.Rxg1+ Kxg1 22.h5 Kf2 23.h6 Rh4 24.Kg6 Kxf3 25.Kg7 Kf4 26.h7 Rg4+ 27.Kh8 Kf5
Is he wrong in stating this? Is his theory outdated?