Nº13 Oleg Pervakov

Draw

Oleg Pervakov (Russia)

wKh3,Nf2,Bg3,Ra7,Pb4,f5,f6/bKh8,Qa3,Ba6,Rc4,Pb5,g7,h7

1.Ng4!
1.fxg7+? Kg8 2.Ng4 Rxg4–+
1.Ne4? Qa1! 2.fxg7+ Kg8–+

1…g6!
1…Rc6 2.fxg7+ Kg8 3.f6 Qc1 4.Be5! Qh1+ 5.Kg3=
1…g5 2.Rd7 Rc8 3.Nh6 Qe3 4.Nf7+ Kg8 5.Nh6+ Kf8 6.Rxh7=
1…gxf6? 2.Nxf6+-

2.Rd7! It is necessary to close diagonal c8-h3 again!
Thematic try: 2.Re7? Rc8! 3.fxg6 (3.Nh6 Qc1–+) 3…hxg6 4.Ne5 Rg8 5.Nf7+ (5.Kg4 Bc8+–+) 5…Kh7 6.Ne5+ Kh6 7.Ng4+ (7.Nf7+ Kh5 8.Re5+ g5–+) 7…Kh5 8.f7 Rh8! 9.Re5+ g5–+
2.fxg6? hxg6 3.Ne5 Bc8+–+
2.f7? Kg7–+

2…Rc8!
2…h5 3.Rd8+ Kh7 4.Rd7+=

3.fxg6
3.Ne5? Qc1–+

3…hxg6 4.Ne5 Rg8 5.Kg4!
5.Nf7+? Kh7 6.Ng5+ (6.Nd6+ Kh6 7.Kg4 Qxb4+! 8.Bf4+ g5 9.Nf5+ Kg6 10.Ne7+ Qxe7–+) 6…Kh6 7.Kg4 Qxg3+! 8.Kxg3 Kxg5–+
5.f7? Qxb4! 6.fxg8Q+ Kxg8 7.Rd8+ Kg7 8.Rd7+ Kf6! 9.Rf7+ Ke6–+

5…Qxb4+ 6.Bf4! Bc8
6…g5 7.Nf7+ Kh7 8.Kh5!=

7.Nf7+ Kh7 8.Ng5+ Kh6 9.Nf7+ Kh7 10.Ng5+ Perpetual check by double check from two white batteries, one of whose pieces is pinned.
The mechanism is similar to the mechanism from the study of A.Stavrietsky (1st prize FIDE Cup, 2021), but it is fundamentally different: with an alternating pin of black queen.