1. Kc6 ! b5 ! ( 1.... a4 ? 2. a3(Rb7) mate in 5 )

2. Rb7 !

2. a3 ? b4 ! 3. a4 ! b3 4. Rb7 b2 ! and mate in 4.

2.... b4

3. Rb5 !!

3. Rb6+ ? Ka7 4. Kc7 a4 ! 5. Rxb4 Ka6 6. a3 Ka5 ! 7. Kc6 Ka6 8. Rxa4 # model mate.

A) 3.... b3

4. axb3 a4

5. b4 !!

5. bxa4 ? Ka7 and mate in 3.

5.... Ka7

6. Kc7 Ka6 !

7. Ra5 # perfect mate.

B) 3.... Ka7

4. Rxa5+ !

4. a4 ? Ka6 ! 5. Kc7 b3 ! 6. Rxb3 Ka7 7. Rb6(b8) Ka8(a6) 8. Ra6(a8) # model mate of Ra6.

4.... Kb8

5. Ra4(a6) b3 !

6. axb3 Kc8

7. Ra8 # model mate.