1.Bd6!
Not 1.Bb4?? Rc7! and White loses: 2.Kxd1 Kb2. Nor does 1.Ba3 work because of 1... Rb7. White must stop the rook controlling the b- or c-files
1...	Rf5
2.Bb4	Rf3
3.Bc5	Rf4
3... Rc3? 4.Bd4
4.Ba3	Rb4
5.Bxb4	1-0
Gutman (1935)