Mate in 20, "Brilliant" in 'Glarean Magazin'

[kgburcham]

Thanks to Walter Eigenmann
"Brilliant" in 'Glarean Magazin'

[d] k4r2/P4P2/Kp1r2P1/1P6/2B4p/1PbpB3/5P2/8 w - -

+M20 1.Bd4 Rd7

[Anil]

Nice position. Rybka 3 seems to be the only engine to get this move under a minute! All others seem to get stuck with Bc5 for a long time.

[lewisg]

Good position. Here is another good test position.

r1b2rk1/1p2q2p/p1n1p1p1/3pP3/4pP1P/2N2NQ1/PPP3P1/2KR3R w - -

How long before your engines see that H5 is clearly winning (i.e. 17. ... Qf7; 18. Rh4 OR 17. ... exf3; 18. hxg6 hxg6; 19. Rh6)?

[Anil]

Good position. Here is another good test position.

r1b2rk1/1p2q2p/p1n1p1p1/3pP3/4pP1P/2N2NQ1/PPP3P1/2KR3R w - -

How long before your engines see that H5 is clearly winning (i.e. 17. ... Qf7; 18. Rh4 OR 17. ... exf3; 18. hxg6 hxg6; 19. Rh6)?

Good position... but the clear win seems to be too deep and involves Knight sacrifice and then finally after 8 moves white gets more than enough compensation for the knight by getting black's a8 rook. Then comes the forced exchanges of queen and rook (by giving checks)... leading to a winning endgame.

For the engines, h5 is tough to find. But, after Qf7, Rh4 is also quite tough (for doubling of rooks on h).

1. h5 Qf7 2. Rh4 exf3 3. hxg6 hxg6 4. Rdh1 Qg7 5. gxf3 Rf7 6. Qh3 Kf8
7. Rh8+ Ke7 8. Na4 Bd7 9. Rxa8 Rxf4 10. Nc5 Qxe5 11. Nxb7 Qe3+ 12. Kb1 Qxf3
13. Qh7+ Rf7 14. Qh4+ Qf6 15. Qxf6+ Rxf6 16. Rh7+ Rf7 17. Rxf7+ Kxf7 18. Nc5 Ke7
19. Rxa6 g5 20. Ra8 *

Lewis, can you share the game from which this position was taken here?