What is the best response to 1...d5

Qxf3 is playable and looks attractive but it's still better for the knight to be on f3 because that way development is smoother and it works for castling kingside quickly. Once white is castled, any Ng5 move will double the pressure on f7 where Qxf3 is more sluggish especially if black castled because then the queen in front wouldn't be as good as a knight, rook, and possibly bishop all teaming up.

after 1.e4 d5 2.d4 it is no longer the Scandinavian but rather the Blackmar-Diemer Gambit, usually reached via 1.d4 d5 2.e4

-- Ozzie

Cmon don't transpose into an opening like that! Just take take the d5 pawn! White then gets a nice easy game with the advantage.

Well it's true. Give me a sound line of the scandinavian that puts serious pressure on white. The ...Qd6 variation? My solution to that is to fianchetto the bishop so that Bf4 can be played. White would have many things then: two tempos off the queen, more development, attacks with a knight on e5, queenside pressure with his bishops, and more space. That is at the very least good for white. It's kind of like a worse variation of the caro kann played to be different because I think it's a little less challenging  than the similar caro kann.

I tend to agree, that very casual play as white against the Scandinavian will much more easily lead to +/= than very casual play as white against the Caro-Kann.

That's what I was trying to tell you in that message yesterday- in case I didn't clear that up properly.

Yes Nytik, I borrowed from our conversation, sorry I didn't give you the proper footnote credit -- but I thought it might be an invasion of privacy.

I like 2...nf6 and if c4 c6 gives good devlopment for the pawn

much stronger for white is 1.e4 d5 2.exd5 Nf6 3.c4 c6 4.Nc3 cxd5 5.d4

Transposing to the Caro-Kann Panov-Botvinnik attack.

So is that why 3...e6 is the better move?

"active" line in the C-K P-B attack. Good luck with that.

The character of the position is defending a d4-style IQP position. I wouldn't characterize it as active, unless you're on the white side. White gets more activity, and black has the better structure.

Just to put it out there, I don't measure tempos in the openings at all.

Having gained tempi in the opening should manifest itself as a lead in development in most cases, should it not?

Yup. And the lead in development should give you a head start in whatever middlegame plan you choose. So it's not that I don't think about it, it's that the variations that I look at will end up being different when my opponent loses tempises.

Xylograph, the 6...Bg4 line with a later 9...Nb6 is one of the more 'interesting' tries for Black.

I recommend the Nimzo-Indian style setup with Bb4:

1.e4 d5 2.exd5 Nf6 3.c4 c6 4.d4 cxd5 5.Nc3 e6 6.Nf3 Bb4

play can continue

7.Bd3 dxc4 8.Bxc4 o-o 9.o-o

and black has a choice among Nbd7 or b6 here, along with the slightly odd-looking Bxc3 right away (if my memory of Games Explorer serves).

If you really want to gambit a pawn, then try the setup with g6. Black typically gambits the d5 pawn "but hopes to get it back with advantage". I don't like this line because it's slightly less sound than the one with Bb4, and if white knows what he is doing then the game can seem almost over before it really begins. At least from the defensive side of an IQP, you get a game to play.

1.e4 d5 2.exd5 Nf6 3.c4 c6 4.d4 cxd5 5.Nc3 g6

Look it up in games explorer, and if you can, search for games where J. Polgar plays white.

Ya, I believe 6...Bb4 is the most reliable way for Black to equalise here; but it still leads to IQP type positions, whereas the ...Bg4 line with ...Nb6 can lead to slightly more unstandard play.

 So what would be your suggestion to someone that does not have enough time to memorize lines from the Sicilian Defense to play against e4?

I am not saying you are wrong about d5 being one of black's weakest replies to e4, however, can you give lines as to how the game might play out for maybe 10-moves which shows how black falls behind by more than +0.50? (Technically, white having the first move should earn him a +0.50 advantage). I guess I am asking where white can earn more of an advantage to black's response d5? Thanks.

Yes, ouachita, I think it's better if you make a stronger argument than simple hand-waving. Not saying you're wrong, but you should give some lines.

I'm personally not so sure that 2... Nf6 is any better than some of the 2... Qxd5 lines, for what it's worth.

1.e4 d5 2.exd5 Qxd5 3.Nc3 Qa5
1.e4 d5 2.exd5 Qxd5 3.Nc3 Qd6
1.e4 d5 2.exd5 Nf6 3.Nf3 Nxd5 4.Be2 etc - white will develop, play c4, only then Nc3 and will have IMO a better position than your typical IQP Panov game.

Actually white having the first move doesn't and wouldn't give whtie a .50 pawn advantage... The general rough rule is that a tempo is worth about a third of a pawn, and all the studies I've doen with engine analysis seem to say that from the first move, white's advantage is even slightly less than this perhaps.

I also wouldn't say that 1...d5 is one of the weakest responses to 1.e4. Actually, as stated flatly that's almost absurd, but I think that he meatn to say that it's one of the weakest reasonable replies, being weaker than 1...e5 1...e6 1...c5 1...c6, etc. It's better than, say, 1...f5, 1..f6, 1...g5, etc. I actually don't even think it's necessarily all that weak, but objectively it isn't all that strong. As for other lines you want to look into, Ozzie would certainly suggest the CK, but if you're looking for something really simple, you might want to pick out a line of the French that you like, or look into the Pirc. If you want something REALLY simple though, I would advise the Scandanavian.