01 Jun 22
The game between Fred Olson (1646) and me (1593) from the Edison (NJ) First Sunday of the Month Quad on May 4, 1975 presented many moments in which pawn tension could have been better handled.
Here is the position after my opponent played 10. f2-f4.
Having played 9...Rb8 as the first step in preparing the ...b5 break, Black should continue along this vein with 10...a6. If White played 11. a4 to inhibit that break and to open the file for White's a-rook in case that break were achieved nonetheless, the continuation might have been as shown in the next chess movie.
Black actually played 10...e6 to prevent 11. f5, reckoning that the weakening of his d-pawn (not to mention the f6-square) could be withstood in a closed position. The fallacy was in believing that White wouldn't soon be able to expose Black's d-pawn, as will soon be apparent.
In the resulting position,
White played 11. Be3, and Black replied 11...Re8, a further prophylactic against f5... because after ...exf5, White's e-pawn would be pinned against the e-bishop. However, although f5... would have given White a space advantage on the kingside, this would hardly be decisive by itself, especially if Black promptly sought counterplay by preparing the ...b5 break. Moreover, neither 10...e6 and 11...Re8 is otherwise useful for Black, whereas both 10. f4 and 11. Be3 are useful for White. Finally, if White were to eventually play f5... and exchange at g6, Black's rook might be better placed at f8 than at e8.
After 11...Re8,
White could have played 12. d4, threatening to win material by 13. dxc5 dxc5 and either 14. Bxc5 or 14. e5 Nh5 15. g4, winning a piece. 12...b6 would protect the c-pawn adequately, but after 13. dxc5, recapturing with the b-pawn would allow 14. Qxd6, whereas recapturing with the d-pawn would again lose material after 14. e5. Therefore, Black would have to reply 12...cxd4 but would face difficulties as shown in the following chess movie.
Black's difficulties can be largely traced to the pawn structure. Imagine that the game had instead gone 10. f4 a6 11. Be3 b5, bringing about the following position:
Suppose that to prevent 12...bxc4 followed by 13...Rxb2, White were to play 12. cxb5 axb5, and White then broke in the center by 13. d4, bringing about the following position:
Protecting Black's c-pawn by 13...Qb6 would invite 14. dxc5 dxc5 15. e5, which would attack the only defender of the d7-bishop. However, Black could reply 13...cxd4 without making his d-pawn vulnerable despite its being on a half-open file, because it would be held by Black's pawn at e7.
In retrospect, 10...e6 severely damaged Black's position by weakening his d-pawn.
In the game after 11...Re8,
the next move-pair was 12. Qd2 e5. White could now have bypassed by 13. f5.
This would be especially favorable for White because the center is locked. Had White played 13. f5, it would have revealed Black's 12th move to have rendered useless the prophylaxis from his two previous moves (which as noted earlier, shouldn't have been undertaken at all).
The continuation might be as depicted in the next chess movie.
White actually played 13. Kh2, and the game continued as follows:
In the position reached in the above chess movie,
White should try to leverage the now half-opened f-file. This suggests the move 15. Bg5, pinning the knight as a target for further attack and threatening 16. Nxd4 (Clearing the second rank with tempo.) 16...cxd4 17. Nd5 Re6 18. Qf2 (Black has no additional units that can defend his knight.) 18...Ng4+ 19. hxg4 Qxg5 20. Qxf7+ Kh8 21. Qxd7.
After 15. Bg5, Black's best try seems to be 15...Nxe2, as White's recapturing with the knight would take that piece further from the d5-square, whereas taking with the queen would permit 16...h6 to break the pin. After 15. Bg5 Nxe2 16. Qxe2, 16...Ng4+ would lose a pawn to 17. Qxg4 (Intending 17...Bxg4 18. Bxd8, winning a piece.) 17...f6 (To regain the piece.) 18. Bxf6 Bxf6. 16...h6 also would lose a pawn, by 17. Bxf6 Bxf6 18. Qf2, hitting f6 and c5 and with a veiled attack at f7.
The game instead continued 15. Bxd4 cxd4 16. Nd5, bringing about the following position.
Black has an opportunity to activate his kingside majority by 16...Nxd5 followed (after either recapture) by 17...f5. Although the exchange of knights would give White a protected passed pawn, it's hard to imagine a scenario where it could safely advance. This is partly because White's e2-knight has hardly any safe moves, and several tempi would be needed to reposition it to an effective square, if there is one.
However, Black played 16...Bc6, with what intent I'm not sure.
Black continued to meander and eventually lost.
Moral: If you judge it necessary to impede the opponent from carrying out a pawn break or other plan, try to accomplish this by
1. Moves that would be desirable anyway (such as developing moves); else
2. Moves that serve no other purpose but at least don't create weaknesses that the opponent can exploit; else
3. Moves that give you exploitable weaknesses but nonetheless seem indispensable.
The above game demonstrates some of the difficulties that can result from disregarding this principle.
(A list of the threads I've initiated at this forum is available at http://www.davidlevinchess.com/chess/RHP_my_threads.htm .)