White is down serious material. He can recoup some of the material right away with 28 e8=Q+ Rxe8 29 Rxe8+ Rxe8 30 Qxe8+ Kh7, but this still leaves white down by two pawns and his back rank is dangerously weak.

I think white has to try for more, and the most immediate threat I see is

28 Be5

Not only does this threaten 29 Qxg7#, the bishop blocks the black queen's access to the king side of the board, and it also gives our king some "luft" in the future by clearing the h2 square.

I think black must play

28...Rg8

This stops the immediate mate. But I think white needs to turn up the pressure. How about

29 Qg6

Now the threat is 30 Qxh6#. Black seems to have but one defensive move...

29...Qc6

It's time to win back some material and exchange down.

30 Bxg7+ Rxg7 31 e8=Q+ Rxe8 32 Rxe8+ Qxe8 33 Qxe8+

Now black has a choice. Move the king or interpose with the rook. I think black should try

33...Rg8

because after 33...Kh7 34 Qe4+ picks up the knight.

34 Qe5+ Rg7

Once again 34...Kh7 35 Qe4+ wins the knight.

This seems correct so far. If we can move the b4-knight, then the bishop can be brought into the game.

a: 29... Qxe5 30. Rxe5 Rge8 + -
b: 29... Qc6 30. Bxg7+ Rxg7 31. e8Q+ Rxe8 32. Rxe8+ Qxe8 33. Qxe8+

My line of thought goes:
28. Be5 Rg8
29. e8=Q Raxe8
30. Bxg7+ Rxg7 (if ...Kg7, then 31. Bf6)
31. Rxe8+ and White wins.

If
29...d2, then
30. Bxg7+ wins again.

28.Qg6 Re1 29.Be5 Nice Tuesday puzzle However ...28.Qg5 busts it

Aha: that Bishop on b1 is doing nothing:28. a3 and Black can't play Qc1because of 29. Qf8+ but Kh7 again is the spoiler

Material: 2B for 2N+R. White can soon play e8=Q, supported by Re1 and Qf7, to regain his R. The Black Kh8 is isolated, and the Black K-side has a weak light-square complex accessible to Qf7. The advance of the Black Pd3 must consider the opening the b1-h7 diagonal for Bb1. The only inactive White piece is Bh2, but the mate-in-1 threat Be5 activates it easily. The move Be5 is desirable also, to create luft, because presently White is vulnerable to back-rank mates.

Candidates (28.): Be5

28.Be5 (threatening Qxg7#)

Black has 2 possible defenses.

(1) 28…Qxe5 29.Rxe5

threatening

29.e8=Q+ Rxe8 30.Rxe8+ Rxe8 31.Qxe8+ Kh2

with all exchanges forced to avoid mate. Then, Qe8 easily stops Pd6 (or Pd7), and Black has nothing to play for. Black can try

29…Rc1+ 30.Kh2 Rxb1 31.e8=Q+ Rxe8

[31…Kh2 32.Qg6#]

32.Rxe8+ Kh2 33.Qf5+ g3 34.Qf7#

The only alternative on move 28… is therefore passive defense.

(2) 28...Rg8 29.Qg6

threatening 30.Qxg7#, 30.Qxh6#, and 29…d2 30.Qh7#

Black cannot respond 29…Qxe5, so defense of Ph6 is the only alternative.

29…Qc6 30.e8=Q

The White Qe8 and Qg6 are now mutually protecting, on a rubber band. The Black Qc6 is burdened with protection of Ph6; the Black Rg8, with protection of Pg7. Black has one R to spare, however.

30…Raxe8 31.Bxg7+ Rxg7 32.Rxe8+ Qxe8 33.Qxe8+ Rg1

It is not until 37.a3 - 9 moves into the combination - that white secures a material advantage. And all the time black has that monster pawn on d3. Swap off all the pieces (eg by 29. Bxg7+?) and this pawn gets ever more dangerous.

Me? I saw 28. Be5 but then failed to see the strength of 29. Qg6. My continuation was the wimpish 29. Ba1 when white has threats against both g7 and e8.

My new toy, Fritz 11, evaluates 29. Qg6 as +3.7, 29. Ba1 as = (0.00) and 29. Bxg7+ as -3.7.

<sniperon G7> Great name, BTW! Fritz 11 rates your line as -3.7 - a decisive advantage to black. You've thrown away your passed pawn and won the exchange. But as you started a rook down, this does not equalise. 31... Kh7 and white has little to show for his adventure.

My usual problem of not analysing in sufficient depth!

Hi, <Once>.

I agree that White does not have a clear-cut material advantage until 37.a3. In my estimation, however, analysis is not required to see that White has a win after 33.Qxe8+ (and I notice that, like me, <dzechiel> discontinued precise analysis then). The Pd3 is dead, the Black pieces are scattered, and Kh8 is exposed to forking checks - all part of the recipe for the White win as it occurred, convenient because forced, but strategically inevitable.

Thanks for giving me credit today, which I appreciate after being bruised, like so many others, by my effort against Tal yesterday :<{

Material: White is down a R and a P, but has the B pair against 2 N. White has a P on the 7th rank, while Black has one on the 6th rank. Black's K has little defense, and the g7 square is weak. Down so much material, White must look for mate threats, either ending in mate, winning a Q or both R's for compensation. The P on the 7th rank is going to be key.

Candidates: a3, e8=Q+, Qxg7+, Qf8+

28.a3 drives the N off the b4 square, likely Nc6, and could capture on d3, putting more pressure towards the Black K. There are problems with this move. Black can ignore it, for instance 28.a3 d2. Or ignore it completely. Even a full N at this stage won't even the material. The a3 pawn will fall after the N moves (Qxa3) and the "pressure" is not forcing. However, this is a subtle move and could be necessary preparation in order to bring the light-squared B to play later. Would really like to have that b1-h7 diagonal covered, because it would create a back-rank weakness for Black. Wishful thinking?

28.e8=Q+ or Qf8+ may also come into play later, but there is no good continuation, despite these being forcing moves.

28.Qxg7+ Kxg7 29.Be5+ easily blunted via Qxe5 30.Rxe5 and Black wins with superior material.

28.Be5 threatening Qxg7# is forcing and looks promising. The Be5 blocks the Black Q from defense on g5, however, it also interferes with the Re1 coming into play.

28.Be5 Rg8

Continuations:
29.Qxg7+ Rxg7
29.Bd4...
29.e8=Q Raxe8 30.Bxg7+ Rxg7 (31....Kh7 mate to follow) 31.Qxe8+ Rg8 29.Bxg7+ Rxg7 (29...Kh7 mate to follow) 30.e8=Q+ Rxe8 (both Qf8 and Rg8 lose Qxf8+ or Qxg8#) 31.Qxe8+ Rg8

The last two transpositions to the same position. One of them may be a blunder.

Having a hard time visualizing a winning continuation in this position. K is trapped at h8. Q is on e8 on light squares. R on g8 defending. The only check available is 32.Qe5+ QxQ 33.RxQ and now the material is R+B vs. R+N+N. If the Re1 moves, Black gets Qc1+.

The problems come when the Q goes to e8 and comes off dark squares. Can't we just bring the R in at e8? Why did I miss that?

28.Be5 Rg8 29.Bxg7+ Rxg7 30.e8=Q+ Rxe8 31.Rxe8+ Rg8 (31...Qf8 just drops the Q) 32.Qf6+ Kh7 33.Re7+ Qxe7 34.Qxe7+ and the material is Q+B vs. R+N+N. The Nb4 is hanging and will probably be forked.

Time to check.

29.Qg6 threatening Qxh6#. Didn't see that. I had the right idea, since this still ends the same as mine with Q+B versus R+N+N. What did I miss? Checking with Fritz...

31.Rxe8+ Kh7 Ouch. Sigh. No cookie for me.