If it is free, take it

In this third-round tournament game, ironically the first turning point is the free material that I did not take on move 19. The variations are slightly tricky, which were enough to confuse me at the time and deter me from taking the a-pawn, but they work out just fine in Black’s favor. That was bad enough, but then I hung a piece for the second game in a row; this time my opponent had plenty of time on his clock and easily converted it. Boo.

[Event “?”]
[Site “?”]
[Date “????.??.??”]
[Round “?”]
[White “Class B”]
[Black “ChessAdmin”]
[Result “1-0”]
[ECO “D15”]
[Annotator “ChessAdmin/Dragon 3.2”]
[PlyCount “57”]
[GameId “488554488640”]

{[%evp 0,57,30,29,19,-10,33,5,22,3,7,7,16,20,7,-19,-16,-33,26,24,29,19,31,-58,-58,-44,-30,-47,-48,-48,-7,-59,-32,-53,-44,-44,-40,-47,-33,-111,-8,-94,236,244,238,211,211,219,269,222,269,272,317,320,314,272,323,337,389,389]} 1. d4 d5 2. c4 c6 3. Nc3 dxc4 4. e3 b5 5. a4 b4 6. Nb1 Ba6 7. Nf3 Nf6 8. Qc2 e6 {good enough for equality.} (8… b3 {would be a slightly better version, kicking the queen back first.} 9. Qd1 e6) 9. Bxc4 Bxc4 (9… Bb7 $5 {is an interesting idea, looking to play …c5 next and open up the long diagonal for the bishop.}) 10. Qxc4 Qd5 {this perhaps commits the queen too early.} (10… Nbd7) 11. Qxd5 cxd5 $11 12. Nbd2 Bd6 {this looks very drawish now.} 13. Nb3 Nbd7 (13… a5 {looks simpler.}) 14. Bd2 a5 15. O-O O-O {played reflexively. We are close enough to the endgame and Black’s king has solid protection in the center, so this is not necessary.} (15… Nb6 $5 {is more active, eyeing c4 and a4.}) (15… Ke7 {would connect the rooks and also protect d6, which later becomes a key problem.}) 16. Rac1 Ne4 17. Rc6 {this is annoying but not actually dangerous.} Rfb8 {bringing the other rook into play and controlling the b-file.} 18. Rfc1 Nb6 {Black should now have at least a small advantage, with the a4 pawn threatened and the knight looking to go to c4.} 19. Be1 h6 $6 {protecting against back-rank tactics, not a bad idea in itself, but it leaves by the waysdie the material on offer and a breakthrough on the queenside.} (19… Nxa4 $1 {of course I saw this, but erroneously thought that White could simply recover the pawn.} 20. Nxa5 (20. Ra1 Nxb2 21. Rxa5 Rxa5 22. Nxa5 b3 $1 $19) 20… Rxa5 $4 (20… Nxb2 $1 $19 {followed by an active retreat to d3 or c4 should win.}) 21. Rc8+ Rxc8 22. Rxc8+ Bf8 23. Bxb4 $18) 20. Nbd2 Nf6 $4 {a hallucination triggered by poor calculating technique. Here I simply forget that the knight was backwards-protecting the Bd6.} (20… Nxd2) (20… Nxa4) 21. Rxd6 $18 Nxa4 {the position is certainly resignable now, but just in case of a reverse blunder I fight on.} 22. b3 Nc3 23. Kf1 Kf8 24. Nb1 Nxb1 25. Rxb1 Rc8 26. Rb6 Ne4 27. Rb5 Rc2 28. Ra1 Rac8 29. Rbxa5 1-0