Ruy Lopez, best reply to Bxc6

dxc6 or bxc6? 

http://en.wikipedia.org/wiki/Ruy_Lopez,_Exchange_Variation

MCO-10 gives 4...dxc6 as standard, 4...bxc6 as "interesting." I don't know why. Usually capturing toward the center is better, but the same recapture is recommended in the Petrov after Black plays ...Nxc3.

OK, I'm not a GM talking but in the Ruy Exchange ...dxc6 is normally preferred (by man and machine) because it opens up the queen AND the light squared bishop. In fact in one mainline, Black will soon thereafter play ...Qd6 and gets a fully playable, good position.

Ruy Exchange is a bit tricky to play for Black and you should know the lines a bit. But if you do, White should obtain no real advantage out of the opening. At the highest level, Ruy Exchange is relatively rarely played nowadays.

The old school would be you try it out in your own games and see which capture which gives you the better play.

Tom, so would you say that an accurate rule of thumb is: "When recapturing  with pawns, capture toward the center unless: (1) it's an opening whereby capturing toward the side frees more pieces, or (2) capturing toward the center opens up a line of attack at your king."?

This is the Petroff  line I mentioned that is standard:

1. e4 e5
2. Nf3 Nf6 {Petroff's Defense.}
3. Nxe5 d6
4. Nf3 Nxe4
5. Nc3 {Nimzovich Attack.} Nxc3
6. dxc3 {Captures away from the center to free pieces.}

P.S.--How about a couple PGNs?

After e4, e5, Nf3, Nc6, Bb5, a6, Bxc6 (which is the line I'm guessing you mean because Bxc6 can be a sideline in a few other Lopez variations) the best play for black is dxc6 because when white plays Bxc6 he is normally aiming to play Nxe5 and the move dxc6 will allow Qd4 forking the e5-knight and pawn and there is no way to defend both and play normally continues (in my own games as black in this line because I don't like using this "win the e5-pawn" idea personally) Nf3, Qxe4+, Qe2, Qxe2, Kxe2 and at this point we enter an endgame in which black has the bishop-pair and rights to castle against the double queenside pawns which I think personally favours black

Okay, this will be a long answer on my part, partially because I play the Ruy Exchange heavily as White.

4…dxc6 is best for a number of reasons.  For one, it aids more in Black’s development of the bishop on c8, while bxc6 keeps the bishop trapped for several moves, especially with the a-pawn on a6.  With rapid development commonly acting as compensation for doubled pawns (as in the 5.Nc3 Petroff or the 3.Nc3, 4.dxc3 variation of the Alekhine), this delay is bad for Black.  More importantly, however, is the resulting pawn structure.  With dxc6, Black is left with two pawn structures, which is perfectly fine, as the queenside pawn structure actually provides good cover for the Black king if he castles queenside.  With bxc6, however, Black is stuck with three pawn structures, and the “middle” one (c7, c6, d7) is especially awkward (and blocking in the bishop, as discussed before).  Furthermore, Black is usually stuck with a weak pawn on c6 (after d7-d6 to free the bishop), and advancing the pawn to c5 can add dynamism to Black’s position but also make that structure a bit more unstable and trickier to defend.  Plus, there’s also the general idea of wanting to castle queenside, as Veganomnomnom said.  Just my general remarks, others can improve on this however they want.

Now, after 4…dxc6, White has a number of options.  The main one is 5.0-0, which is also best, but let’s look at some other options first:

1. 5.Nxe5? is a complete patzer’s move, and Black can quickly gain an advantage after 5…Qd4! 6.Nf3 Qxe4+ 7.Qe2 Qxe2 8.Kxe2, where his bishop pair and White’s displaced king give Black more than enough compensation for the doubled pawns.

2. 5.d4?! is best responded to with 5…exd4, and after 6.Qxd4 (6.Nxd4?! gives Black a decent advantage after 6…c5 followed by 7…Qxd1+) Qxd4 7.Nxd4 Black can have a slight advantage with 7…Bd7 followed by 0-0-0, where he has a good game.

3. 5.Nc3!? is an okay move, and I like the idea of 5…Qd6, because you can get positions similar to 5.0-0 Qd6 (my main recommendation for you).  Admittedly I’m still working on analysis here, maybe others can help you here.

By far the most common move is 5.0-0, getting the king to safety while remaining somewhat flexible in his plans.  Here Black has a number of options:

1. 5…Bg4 is one of the more common choices, but quite honestly I don’t like this move, because I feel that White gets an advantage in many of the lines:

   1. 5…Bxf3?! just hands over the bishop pair to White after 6.Qxf3, which is a big part of Black’s counterplay.  Not recommended.

   2. 5…h5 leads to positions that have been heavily analyzed, and it looks like White gets an advantage in the end for almost all of the options.  (And for those wondering why not 6.hxg4?, Black is forced to give up his knight after 6…hxg4 in order to avoid mate.  It’s a famous trap.)

   3. 5…Bh5 has been controversial, leading to a gambit after 6.g4 Bg6 7.Nxe5, where Black’s counterplay is based on the weak f4 and h4 squares and White’s weakened kingside.  My personal opinion is that Black doesn’t have quite enough counterplay for the pawn, though the defense can sometimes be tricky against a creative opponent.

2. 5…f6 is the other most common choice.  While others will disagree with me, I have never believed that it’s Black’s best option, as I personally believe that the two lines that stem from this after 6.d4 (exd4 and Bg4) give White a slight advantage.

   1. 6…exd4 7.Nxd4 c5 8.Ne2! (8.Nb3 is playable, of course, but I’ve never liked the positions that resulted from it) Qxd1 9.Rxd1 gives White a more flexible position with a slight development advantage and more influence in the center.  I’ve played many games with this line as White (and I will admit I’m slightly biased with this line), and in the majority of them I’ve felt that I had a nagging edge throughout the entire game based on the opening.

   2. 6…Bg4 is the more fighting chance, but after 7.dxe5 Qxd1 8.Qxd1 fxe5 9.Rd3 I feel that White is slightly better placed with a better pawn structure, while 8…Bxf3?! 9.gxf3 fxe5 Black has given up his bishop pair to damage White’s pawn structure, but I don’t believe it’s quite in Black’s favor. 

3. My personal recommendation is 5…Qd6.  It prepares queenside castling, and it also adds a bit of dynamism to Black’s position since the queen can swing over to anywhere she’s needed.  Plus, White can’t really exploit Black’s early queen development, and Black usually can get a good game.  (Note: 6.d4?! leads to 6…exd4, which leads to similar positions as 5.d4?! where White has the extra move of Nc3.  Even with this extra tempo, Black should still be fine)  Others can elaborate on this as well, I know pfren has mentioned it several times before.

There are other suggestions as well (especially what I play, 5…Qf6), but I’ll leave it at that for now, as I’m fairly busy right now.  Hopefully this helps.

Thanks, drybasin, for the detailed information. Although I don't play the Ruy Lopez as White or Black, I do encounter enough double e-pawn openings as White or Black (Petroff, Four Knights, Three Knights, Philidor's, Damiano's, etc.), some of which transpose into Ruy Lopez lines, that I'm finding I want to learn more about the Ruy Lopez ideas.

alright lads

Sqod, I'm definitely not a chess authority to formulate any accurate rule of thumbs. But I'll try to reply something...

drybasin and the other chaps have all written good comments. This is actually a really good thread, which happens rarely enough on chess.com

In the Ruy Exch., the capture ...bxc6 is basically a conscient decision by Black to gambit a pawn. White can now take the nice e-pawn and Black has to have a concrete plan what to do now. I'm not saying it is the end of the world, surely not, but practice seems to indicate (simply from looking at the number of database games played in that line) that Black players do not trust as much in whatever their compensation may be after ...bxc6. White is also not obliged to take the pawn. But the burden is on Black to prove his point, i think.

In any case Black's pawn structure looks messed up. He has 3 islands now. Queenside castling seems unlikely and after any early ...f6, the kingside would be weakened as well. I think it just gives White many targets to go after even if he returns or has to return the pawn at some point.

As to your 2 rules, yeah, I would think these appear sensible. Not sure (not enough experience) if one can generalize it like this in all situations though. In the end one has to look at each position individually as chess is just such a concrete game.

Again, please take my words with some caution as I am not a strong player.

Thanks for the replies, very useful for a patzer like me. Dxc6 seems definitely better and I'm gonna try castling queenside more as black.

4...bxc6 is playable with best play, but that's about it.  In fact, the key words are "with best play," which is much easier said than done.  Black has structural problems and the issue of the bishop on c8, as mentioned in my page-and-a-half reply (yes, I typed it out in Microsoft Word, it WAS that long), while White has an easier position to handle and no real problems, especiallly after the "main line" 5.0-0 d6 7.d4.  It might work as a surprise weapon, but really only at lower levels or in blitz, and by someone who really knows the theory well.  If you want to play 4...bxc6, no one's stopping you, but why waste time and effort learning how to get a playable position when you can get a better position with 4...dxc6 and an easier game?