Section A1 – Win
1.a3 !
{The quiet pawn move offers the white king an escape route from the
first rank weakness. It also prepares White’s own checkmate attack. In
fact, White could instead lose on the spot (whereas 1.Ka1 Rg1 2.Nb1,
1.Rd6 and 1.Nb3 are easy draws):}
( 1.Rxc5 ?? Rg1 -+ )
( 1.b3+ ?? Ka3 -+ )
( 1.c3 ?? Ne3 -+ )
( 1.Kc1 ?? Rg1 -+ )
( 1.Nf1 ?? Rg1 -+ )
1…Nc3+ !
( 1…Rg1 2.Ka2 +- )
( 1…Rg5 2.Ne4 ! Nxe4 3.Ra6+ Ba5 4.Bxe4 Rg1 5.Ka2 +- )
( 1…Rg2 2.Ne4 Nxe4 3.Ra6+ Ba5 4.Bxe4 Re2 5.Bf3 Re1 6.Ka2 +- )
( 1…Nxb2 2.Kxb2 Rxa3
( 2…Re3 3.Rxc5 Bf6+ 4.c3 +- )
( 2…Rg2 3.Ne4 Nxe4 4.Ra6+ Ba5 5.Bxe4 +- )
3.Rxc5 Bf6+ 4.Kc1 Ra1+ 5.Nb1 Be7 6.Rc3 Bg5+ 7.Kb2 +- )
2.bxc3 Rxc3
( 2…Kxa3 3.Ka1 ! {enabling Nb1} 3…Rg5 4.Rc8 !
( 4.Nb1+ ? Ka4 = )
4…Ba5
( 4…Bf6 5.Nb1+ Ka4 6.Bd5 !
( 6.Bc6 ? Ka5 = )
6…Rxd5 7.Ra8+ Na6 8.Rxa6# )
5.Nb1+ Ka4 6.Bc6 +- )
3.Kb2
( 3.Nb3 ? Rxb3+ ! 4.cxb3+ Nxb3 5.Ka2
( 5.Ra6+ Na5 ! = )
5…Be7 ! 6.Ra6+ Na5 7.Be4 Bxa3 8.Bc2+ Kb4 = )
3…Ba5
( 3…Rxa3 4.Rxc5 Bf6+ 5.Kc1 Ra1+ 6.Nb1 Be7 7.Rc3 ! Bg5+ 8.Kb2 +- )
4.Nb3 !
( 4.Rd6 ? Rxa3 5.Rd4+ Bb4 = )
4…Nxb3
( 4…Rxc2+ 5.Kxc2 Nxb3 6.Kb2 +- {or 6.Ra6 +-} )
( 4…Nd3+ 5.Ka2 ! Rxc6 6.Bxc6 +- )
5.Rc4+ !!
{and now, as 5…Bb4 6.Rxb4+ wins pragmatically for White, there are
two nice checkmate finishes, each of them mobilizing one of the two,
up to this point, immobile white pieces.}
5…bxc4
( 5…Rxc4 6.cxb3# )
6.Bc6# 1-0