Chess Opening Theory/1. d4/1...d5/2. c4/2...c6/3. Nc3/3...e5

= Winawer Countergambit =

3...e5
Black offers a gambit pawn in order to develop more quickly, as well as displacing White's knight. If the gambit is accepted, Black usually regains the pawn but more than returns the time: after 4. dxe5 d4 5. Ne4 Qa5+ 6. Bd2 Qxe5 7. Ng3, Black has his pawn back, but Nf3 is coming with tempo, and it is white who has the greater development. An alternative is 6. Nd2, after which Black is best not capturing on e5 immediately, but instead playing 6...Nd7, preparing something like 7. Ngf3 Nxe5 8. Nxe5 Qxe5. The old line 6. Nd2 f6!?, making the gambit sincere, has been analyzed by Schiller, building on work by Silman and Donaldson, but has never been played at the highest level.

Of course, White can also capture on d5 before considering the gambit: 4. cxd5 cxd5 and now any of 5. dxe5, 5. Nf3, 5. e3, and even 5. e4 are playable. 5. dxe5 gives Black an isolated queen's pawn, but after 5...d4 6. Ne4 Qa5+ 7. Nd2 Nc6 8. Nf3 Bg4 he will regain his gambit pawn at the cost of the bishop pair, with the d pawn potentially becoming passed after e.g. 9. g3 Bxf3 10. exf3 Qxe5 11. Qe2 Qxe2. 5. Nf3 gets kicked around twice by 5...e4 6. Ne5 f6 7. Qa4+ Nd7, with complex, unclear positions after either 8. Nxd7 Bxd7 9. Qb3 Bc6 or 8. Ng4 Kf7. 5. e3 allows Black to equalize with either the space-gaining 5...e4 or simply 5...exd4. 5. e4 is perhaps the strongest of White's fifth-move choices, and is always followed with 5...dxe4. Then the main continuation is 6. Bb4+ Bd7 7. dxe5 Bb4 8. Bd2 Bxc3 9. Bxd7+ (9. Bxc3 would be a losing mistake) Nxd7 10. Bxc3 Nc5, offering a queen trade while threatening ...Nd3+. 6. d5 bears mention mainly for the historic game Marshall-Winawer, 1901 rather than any great strength.

Finally, White can decline the gambit immediately with either 4. Nf3 or 4. e3. After 4. Nf3, Black equalizes with 4...exd4, or can try for more with 4...e4, where after 5. Nd2 Nf6 6. e3 a reversed French results. 4. e3 is best met with 4...exd4 5. exd4 Nf6. 4. e3 e4 results in a reversed French, but unlike the previous example, White can put the extra tempo to immediate use with 5. Qb3 etc.

Theory table
'''1. d4 d5 2. c4 c6 3.Nc3 e5'''