Puzzle of the week #136

Chess Diagram: 

[Event "Puzzle #136"][Date "2010.10.10"][Result "0-1"][SetUp "1"][FEN "5rk1/pp3pbp/2rp2p1/3Q4/4P3/2P2q1P/PPB5/1K1R3R b - - 0 1"]

Last week's position started a series of puzzles from games played during this year's 39th Chess Olympiad. Looking at the answer below you can see how important each move/ decision is in any position. This time we have our first level 6 puzzle: opposite colour position with both Kings very much defended. A quick look at it shows that White clearly has more space and semi-open files to use for his Rooks. Black seems pretty much limited to an easy defence without headaches. What else of importance is here? Can you see anything? Your tasks:
a) Identify other important aspects of this position not mentioned so far
b) Black to move and win. Yes, you read it right!

Total available points for this puzzle is 20. The answers will be published next week together with puzzle #137.

Puzzle #135 solution:
Game GM Mchedlishvili (Georgia) - Podolchenko (Belarus) @ 39th Chess Olympiad 2010 Khanty Mansiysk, Russia. Here are a couple of answers:
GM Kevin Spraggett (CAN):
After a tough struggle, Black finds himself a bit better. The White e-pawn is going nowhere, and Black's passed e-pawn looks much more alive and dangerous. Here Black can play solidly and cautiously with 46... Qf6, keeping control of the position, and maintaining the better chances. However, Black felt that he might have better chances if he keeps his Queen on the board, so he innocently played 46...Qe5?? Under normal circumstances this would be a good move, but here White has an incredible move that turns the tables! White played as shown in option 2 below. The GM from Georgia has prevailed when his opponent missed the key aspect of the position.
Material: even.
King safety: about the same, since neither King is attacked.
Position: White has a pawn on the 7th rank which can be dangerous to Black. Black has a passed pawn but it is not as advanced. Both passed pawns are isolated and vulnerable. However White's Rook is on the 7th rank as well, supporting its pawn. Black's Rook is stuck on the back rank.
Conclusion: White is better.
Outcome for White - White hopes to force the pawn through to a Queen and win.
Outcome for Black - Black hopes to:
1) Win White's passer and lose his own for a draw;
2) Win White's passer and keep his own, push it and try to win.
b) See solution

[Event "Puzzle #135"][Date "2010.10.04"][Result "1/2-1/2"][SetUp "1"][FEN "4r3/R3P1kp/1p4p1/8/4p3/P1q4P/6P1/5Q1K b - - 0 1"]{Option 1} 1...Qf6 ({Option 2} 1...Qe5?? 2.Qf8+ Rxf8 3.e8=Q+ Kf6 4.Qxf8+ {White wins}) 2.Qxf6+ Kxf6 3.Rb7 Rxe7 4.Rxb6+ Kf5 5.Kg1 e3 6.Kf1 Ra7 7.Ke2 Rxa3 8.Kf3 {We have a draw}

Correct solutions:
Jeffrey - 25 points
Alex - 22 points
Nathaniel - 18 points
Frank - 12 points

Karl, Jeffrey - 175 points
Rick - 156 points
Frank - 114 points
Owen - 95 points
Edwin - 72 points
Alex - 59 points
Nathaniel - 40 points


Double trouble