09 Sep '21 17:05>
The book How Purdy Won, starting on page 37, gives Purdy's notes to his game against M. E. Goldstein (White) from the inaugural Correspondence Championship of Australia, which started in 1937. The following position was reached after 21...Q(c7)e7:
Purdy writes, "If 22 Re3, Kh8 followed by ...Rg8, etc."
However, after 22. Re3 Kh8 23. Rh3, 23...Rg8 would allow 24. Qxh7+! Kxh7 25. Nf5+ Kg6 26. Nxe7+ Kg7 27. Nxg8 Kxg8, when Black lacks sufficient compensation for the exchange. (See next diagram for this sequence.)
I had first thought that after 22. Re3 Kh8 23. Rh3, Black could play 23...Bxg4, intending to meet 24. Nf5 by 24...Bxf5 25. exf5 Rg8+ 26. Kf1 (26. Kh1? Qb7+ 27. f3 Rb1+) 26...Rg7. Then I realized that 23...Bxg4 would lose a piece after 24. Rg3! Rg8 25. Kh1 followed by 26. Rag1 and then 27. Rg7 if the bishop flees. But the silicon analyst brought to my attention that after 25...Qe6 26. Rag1 Rbb8 (unpinning so that 27. Nf5 could be met by 27...Bxf5 28. exf5 [28. Rg7? Bxe4+] 28...Qxf5 29. Rg7 Qf3+) 27. f3, Black would emerge with three pawns for the piece by 27...f5! 28. Qxe6 fxe6 29. fxg4 fxe4, which seems about equal. (See next diagram for the sequence in bold.)
White actually played 22. Nf5 (instead of 22. Re3), and a draw was agreed after 22...Bxf5 23. gxf5 Qf8.
Purdy writes, "If 22 Re3, Kh8 followed by ...Rg8, etc."
However, after 22. Re3 Kh8 23. Rh3, 23...Rg8 would allow 24. Qxh7+! Kxh7 25. Nf5+ Kg6 26. Nxe7+ Kg7 27. Nxg8 Kxg8, when Black lacks sufficient compensation for the exchange. (See next diagram for this sequence.)
I had first thought that after 22. Re3 Kh8 23. Rh3, Black could play 23...Bxg4, intending to meet 24. Nf5 by 24...Bxf5 25. exf5 Rg8+ 26. Kf1 (26. Kh1? Qb7+ 27. f3 Rb1+) 26...Rg7. Then I realized that 23...Bxg4 would lose a piece after 24. Rg3! Rg8 25. Kh1 followed by 26. Rag1 and then 27. Rg7 if the bishop flees. But the silicon analyst brought to my attention that after 25...Qe6 26. Rag1 Rbb8 (unpinning so that 27. Nf5 could be met by 27...Bxf5 28. exf5 [28. Rg7? Bxe4+] 28...Qxf5 29. Rg7 Qf3+) 27. f3, Black would emerge with three pawns for the piece by 27...f5! 28. Qxe6 fxe6 29. fxg4 fxe4, which seems about equal. (See next diagram for the sequence in bold.)
White actually played 22. Nf5 (instead of 22. Re3), and a draw was agreed after 22...Bxf5 23. gxf5 Qf8.