Slight Difference In A Position

I'm working through Practical Chess Exercises by Ray Cheng.



(Diagram 13) Black To Move

I studied this position for a little while and debated two moves.

A. 1. ... Na5 and if 2.f4 (to activate the g2 bishop) then 2. ... e4. 2. ... e4 is in fact
not best. 2. ... exf4 is correct with a big edge to black. Therefore, 2.f4 isn't correct either. I still don't see what's wrong with 1. ... Na5.

The other move I studied was ...

B.1. ... e4 (!-Cheng) 2.fxe4 Ne5
I'll quote the author here. "1. ... e4! 2.fxe4 Ne5. Black gets an outpost for his knight, the e-file (with targets) for his rook, and greater scope for his bishop. White's light-squared bishop is obstructed by his own pawn on e4, however."

That's all true but ... Black wins a pawn in line A. and sacrifices one (temporarily) in line B. After 1. ... Na5, white is doing all that much either.

I wondered how one could be better than the other.

After plugging the position into an engine, even the engine barely gives preference to one over the other (I think it did in fact like 1. ... e4.).

Is either move acceptable or is there really such a huge difference that makes 1. ... e4 preferable?

I'd love other player's thoughts.

Originally posted by paulbuchmanfromfics
I'm working through Practical Chess Exercises by Ray Cheng.

[fen]r2br1k1/1p3pp1/1pn4p/2p1p3/2P5/P1P2PP1/4P1BP/1RB1R1K1[/fen]

(Diagram 13) Black To Move

I studied this position for a little while and debated two moves.

A. 1. ... Na5 and if 2.f4 (to activate the g2 bishop) then 2. ... e4. 2. ... e4 is in fact
not best. 2. ... exf4 ge difference that makes 1. ... e4 preferable?

I'd love other player's thoughts.

the only reason that i can see is that you need the knight to blockade the pawn, which is not possible with the Rook, because the bishop can come to f4 with tempo, i dunno, im just a Noob. It seems to me that the position should remain closed on account of whites two bishops, for if the bishop gets loose it could find a home on the a2-g8 diagonal and white may be able to do something down the f file, if it ever cracks open. this is probably just bumf, but these are my thoughts anyhow, i do think ...e4 is better, trying to keep the bishop imprisoned 🙂

After plugging the position into the computer what it came up with is that after 1...Na5 white can play 2.e4. Then after 2...Nxc4 3.Bf1 chasing the knight away. With 1...e4 2.fxe4 Ne5 you get the outpost for your knight and white's pawn stucture is worse with the doubled e pawns. So even though the computer evaluates the moves as almost equal perhaps letting white play e4 and keeping his king side pawns intact makes 1...e4 better?

On a side note, 1...Ra4 was a third option found by the computer to be equally as good as the other two moves.

Originally posted by paulbuchmanfromfics
I'm working through Practical Chess Exercises by Ray Cheng.

[fen]r2br1k1/1p3pp1/1pn4p/2p1p3/2P5/P1P2PP1/4P1BP/1RB1R1K1[/fen]

(Diagram 13) Black To Move

I studied this position for a little while and debated two moves.

A. 1. ... Na5 and if 2.f4 (to activate the g2 bishop) then 2. ... e4. 2. ... e4 is in fact
not best. 2. ... exf4 ...[text shortened]... ge difference that makes 1. ... e4 preferable?

I'd love other player's thoughts.

Its all about finding the optimal squares for your pieces. The black knight would much rather be posted on e5 than on a5. Surely you get to c4 from both squares but the pawn on c4 is not so important in this poisiton, but the activity of the knight on e5 compared to a knight on a5 is huge.
And one more advantage is, you keep whites pieces unactive and create more weaknesses in his position.

In your line A, whats so bad about f4 for white. You say that exf4 is a big advantage for black, but all i see is 2 bishops becoming a lot more active that initially, after Bxf4. Black might still have an advantage but i still feel you give white fighting chances by activating the bishops and opening lines for whites rooks (f7 is suddenly weak with a white bishop coming to d5).

I dont have an engine with me now, so this is just at the top of my head.

I would play 1...e4 since it seems positionally forced.
I don`t calculate variations to arrive at that decision.
I just think that if I don`t play ...e4 white will play e4 and then poof its too late for me to play it.