To protect the identity of the players involved, I have replaced their real names with pseudonyms.
Mohawk vs Salamander
Black Knights Internal Tournament 2014, Round 16
1. d4 d5
2. Bf4 Bf5
3. e3 Nc6
4. Bd3 Bxd3
5. Qxd3 e6
6. Nf3 Nf6
7. O-O Bd6
8. Bxd6 Qxd6
9. a3 O-O
10. Nbd2 Rfe8 (D)
|Position after 10... Rfd8|
The game resembles a quiet form of the Queen's Gambit Declined; in most positions like this Black usually places his knight on d7 rather than c6, so as to clear the way for a future c5 pawn thrust.
11. c4 dxc4
The semi-open c file will become an important battleground for both sides.
13. Nce5 is possible, but after 13... Nxe5 14. Nxe5 c5 (exploiting the hanging position of White's Queen) 15. Rfd1 Rac8 Black prepares to take control of the c-file that will open up after the exchange.
14. Qc2 Qe4
A very interesting alternative here will be 14... Ne4 15. Nfe5 where the position becomes rather messy, with both sides preparing to undermine the enemy outposts with f3 and f6 respectively. Now if Black decides to do this immediately with 15... f6!? then the reply suggested by Fritz is 16. Rac1 (D)
|Position after 16. Rac1|
It looks like a passive move, but in fact 16. Rac1 is a very sneaky attempt by White to exploit both the semi-open c-file and the soon-to-be-opened d-file. White's Queen and Rook assist the e5 knight in making an indirect attack on Black's Knight, which is in turn guarded by only 2 defenders and pinned to a hanging pawn behind him. Furthermore, White's d-file rook is also looking threateningly at the Queen on d5, which is already overloaded trying to babysit both her knights!
So for example after 16... Nd6 (16... fxe5? 17. dxe5 and the threat along the d-file materializes; Black must give up either his Queen or Knight) 17. Nxd6 Rxd6 18. Nxc6 Rxc6 19. Qa4 (another X-ray, looking at the unprotected rook on e8!) Ra8 20. Rxc6 Qxc6 21. Qxc6 bxc6 the resultant endgame is better for White since he has the better pawn structure.
So instead of 15... f6 a better continuation for Black might have been 15... Nd6 16. Nxd6 Rxd6 before preparing for a f6 thrust later on.
15. Qxe4?! Nxe4 allows White to centralize his knight with gain of tempo.
16. Rxc2 e5
|Don't look my brothers, there's gonna be lots of bloodshed!|
18. Nxd4 Nxd4
19. Rxd4 Rxd4
20. Rxd4 h6
21. h3 b6
22. Rd3 Ne4?
Looks active, but this also relinquishes control of the d7 square and allows White's rook to invade the 7th rank! The alternative suggested by Fritz was 22... b5 23. Na5 c5 24. Nc6 a6 and although White seems more aggressive, the endgame still looks rather drawish.
23. Rd7! (D)
|Position after 23. Rd7|
Remember how quite some time ago we saw an example of the power of a rook on the 7th rank (http://nushsblackknights.blogspot.sg/2013/12/revising-basic-rook-endgames-part-3.html)? Here we go again: The rook on the 7th rank fences off the enemy king, attacks the enemy's vulnerable pawns, and forces the opposing rook to relegate to a passive role of defending the pawns. And by now, we should all know the superiority of active rooks over passive ones.
24. Ne5 f6
The tactical blow that decides the game in White's favour: The dual threat of Nxa8 and Ne7+ has no good reply.
26. Ne7+ (D)
|Position after 26. Ne7+|
After 26... Kf7 27. Nxc8+ Nxd7 28. Nxa7 White wins a pawn and gets the better endgame.
I love this apparently simple, yet so instructive game that clearly illustrates the theme of the rook on the 7th rank.