jprante (2152) on 20-May-07:
Here, the strongest move is a simple pawn move: 33. .. d4!!
Black must immediately react to 34. .. Ng3 followed by 35. .. Qxg2 with losing the Queen and chekcmate. The best method to do this is 34. Qb3, but Black can respond with 34. .. Qf4 35. Rcf1 Qe3! 36. Qxe3 dxe3 and White is in zugzwang. After exchanging all material 37. h4 Ng3 38.Kh2 Rxg2 39.Rxg2 Nxf1 40.Kg1 Bxg2 41.Kxg2 Nd2! Black can lock out the King and Black can promote the e pawn to a Queen.
archduke_piccolo
(2340) on 20-May-07:
A very similar plan might have been to retreat along the g1-a7 diagonal instead, with the same idea in mind: 33...Qa7, or better, maybe, 33.Qd4. Suppose White were defend by 34.Rgf1 then 34..Nf2ch 35.Rxf2 Qxf2 36.Qg3 (36.Rg1 Re1 is curtains, but Qg3 stops ...Re1 or ...Qe1ch as well as the mate on g2) Qxg3 37.hxg3 d4 with an easy win (the actual game would probably have followed this line if White had played 34.Rgf1 in response to 33....Qf6). If White decides not to give up the rook on f2, then a spectacular smothered mate results: 33...Qd4 34.Rgf1 Nf2ch 35.Kg1 Nh3ch! 36.Kh1 Qg1ch! 37.Rxg1 Nf2# (This sort of mating sequence is well worth learning as part of one's technique. It's surprising how often the motif crops up! I won a blitz game on GK with it early last year...). The only other available defences seem to be pawn moves: (A) 33...Qd4 34.g3 Nf2ch 35.Kg2 Ng4ch and mate next, or (B) the other pawn move - 34.h3 Nf2ch 35.Kh2 Re3 and (a) 36.Qa2 Qe5ch 37.g3 Ng4ch 38.hxg4 Re2ch wins the Q. To prevent ...Qe5ch, White might try (b) 36.Qa1 Qf4ch 37.g3 Qf5 (i) 38.g4 Qf4ch 39.Kg2 Qf3ch 40.Kf1 Ne4# or (ii) 38.Kg2 d4ch 39.Kf1 Qd3ch 40.Kxf2 Qe2#
The other rook defence (34.Rcf1 Nf2ch) again leaves White a piece and several zillion pawns down the stank. ***
Note that retreating the Q along the diagonal is not "better" than the retreat anong the file, since the likeliest continuation for both (34.Rgf1) converges to the same thing after Nf2ch (34.g3 also leads to a quick loss by 34...Nf2ch 35.Kg2 Ng4ch 36.Kh3 Rxh2ch 37.Kxg4 Qf5#; 34.h3 Qf4 looks strong. Further, after 33...Qf6 if White moves the Q off the 3rd rank ...Ng3ch leads to a quick mate by ...Qh6.
jprante's suggestion 33...d4 is also good, but I hesitate to call it the "strongest", since the moves already discussed are themselves fairly immediately decisive. Fact is: White is already busted. After 33...d4 34.Qb3 Qf4 35.Rcf1 Qe3 36.Qa4ch Kd8!! 37.Rf3 Nf2ch 38.Rxf2 Qxf2 39.Qd1 and White is just as hopelessly placed as in the other lines...
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