5...Bb4 6.Bc4 d6
Black intends to swap off the knight on c3, and plays 6...d6 so as to prepare ...Ng8-f6 without the knight getting kicked with e4-e5. White's most reliable reply is to attack f7 with 7.Ng5. 7.Qb3 and 7.0-0 lead to complications but may not give White enough compensation. 5...Bb4 others 6.Bg5 is an interesting alternative, but 6...Be7!? is hard to meet. After 6.Bc4, 6...Bxc3+ 7.bxc3 d6 will transpose to 6...d6 in most cases. Alternatives are not as challenging. 5...d6 6.Bc4 Nf6 Black aims to use the bishop on f8 more defensively, putting it on e7. White's most reliable response is to attack f7 with 7.Qb3 here, and complications quickly break out. 5...d6 others White has good chances of an advantage if Black doesn't play 6...Nf6. Instead of 6.Bc4, 6.Bb5 contains a few tricks, but is less likely to give full compensation for the pawn. 5...Bc5 6.Bc4 d6 This Giuoco Piano-style defence has generally been underestimated. 6.Bc4 sets up the threat of Bxf7+ followed by Qd5+ and Qxc5. 6...d6 prevents this by protecting the bishop. Here the usual attacks on f7 don't work so well for White but White can get compensation for the pawn by attacking on the dark squares with 7.Bg5, or 7.0-0 and then 8.Bg5. 5...Bc5 others Again if 6.Bg5 Be7!?. After 6.Bc4, alternatives to 6...d6 are rather sub-optimal. 5th move alternatives for Black Black has some other decent options but none of them are a serious test of White's gambit. |
5...cxb2 6.Bxb2 Bb4+
The most theoretically critical response, but tricky to navigate over the board. White's best is 7.Nc3 Nf6 and White then chooses between 8.Qc2 with the aim of castling queenside and a h-pawn hack, or 8.0-0 with a more positional approach, aimed at pressuring the black kingside. 5...cxb2 6.Bxb2 d6 Passive but more solid. I think White probably has two pawns' worth of compensation after 7.Qb3, 7.0-0 or 7.Nc3, but the resulting positions are hard to assess. 5...cxb2 6.Bxb2 others Other options do not seriously test White's double pawn sacrifice. 5...Bb4 This doesn't work too well as both 6.0-0 and 6.bxc3 are stronger than 6.Nxc3. 5...Bc5 Here 6.Bxf7+ followed by Qd5+ and Qxc5 may be superior to 6.Nxc3. 5...Be7 Here 6.Qd5 is tempting, but it is not clear if it is any better than 6.Nxc3. Both moves are probably slightly better for White. 5...d6, 5...Nf6 Here White should transpose into Accepted I lines with 6.Nxc3. Otherwise the plan of ...Nf6/d6, ...Be7 and ...0-0 gives Black a solid position. |
4...d5Capablanca Variation - 5.exd5 Qxd5 6.cxd4 Bg4 7.Be2 Bb4+ 8.Nc3 Bxf3 9.Bxf3 Qc4
As introduced in Marshall-Capablanca, Lake Hopatcong 1926. White should arguably avoid this line as it tends to lead to rather level endings. White avoids Capablanca's line: 7.Nc3, and if 7...Bb4 not 8.Be2 A way of avoiding this line for White, which should also be equal with best play. It can lead to a tricky and double-edged ending if Black goes 7...Bxf3. 6th and 7th move alternatives for Black Coverage of what happens if Black doesn't aim for Capablanca's line. White tends to score well in practice in these lines, even though some of them are objectively equal. 5th move alternatives 5.Bd3 may be playable for White and may have a fair amount of surprise value. Other moves such as 5.e5 and 5.cxd4 are somewhat dubious. |
4...others4...Nf6 5.e5 Nd5
Probably the most solid alternative declining line to 4...d5, though it doesn't equalise with as much certainty. 6.Bb5, 6.cxd4 and 6.Qb3 are the main replies. 4...Nf6 others Mostly focusing on the double-edged line 5.e5 Ne4!?, which is counterattacking but White can get some advantage against it. Alternatives to 5.e5 are not convincing. 4...Nge7 Black intends 5...d5, and after 5.cxd4 d5 Black equalises, but with 5.Bc4 d5 6.exd5 Nxd5 7.0-0 White can get some initiative, and possibly a slight edge. 4...d3 This "pushing past" move is solid but leads to passive positions for Black. 4...others Other moves are not challenging for White, and most of them allow White to get a strong two-pawn centre. 4...Qe7 is well met by 5.Bd3, and 5.cxd4 Qxe4+ is also fine for White. |