Edit: My mind played a trick on me after the fact. As Akavall notes in a comment, the Chadaev-Carlsen blitz game that I mention below actually proceeded 1. e4 g6 2. d4 Nf6 3. Nf3, a different gambit than the one my question asks about. So please ignore the references to Chadaev-Carlsen in reference to the Roscher Gambit here. (Incidentally, this means that Carlsen didn't buck the trend of highly-rated players avoiding 3. ... Nxe4 in the Roscher Gambit; see below.)
The Roscher Gambit goes as follows:
[FEN ""]
- e4 d6 2. d4 Nf6 3. Nf3
I just saw Nikolai Chadaev convincingly defeat Magnus Carlsen at the World Blitz Championship using this line (where Carlsen accepted the gambit with 3. ... Nxe4). I realized I've basically never seen this gambit, and that I know nothing about it. (I even had to look up a name for it to ask this question.)
It is very seldom played, and especially so among highly-rated players: my database of 5.2M games contains a mere 99 games reaching the position after 3. Nf3, with the average White (respectively, Black) rating in the games being 1953 (1976). But there are 7 games in which 2400+ players tried the gambit as White against equally strong competition (and 2 games with 2500+ players). The most popular response over all games is indeed the obvious 3. ... Nxe4, being chosen in 46 of the 99 games. (Second most popular is continuing in Pirc Defense fashion with 3. ... g6; these two moves account for almost all the games, 83 of 99.)
All of that is about what I would expect. But, interestingly, in the games I have in this line with the highest-rated players, Black consistently avoids 3. ... Nxe4, preferring the 3. ... g6 Pirc approach, or instead aiming for the Philidor with 3. ... e5 (or 3. ... Nbd7 followed by 4. ... e5), Czech Defense with 3. ... c6, or even the Nimzowitsch Defense with 3. ... Nc6. The highest rated player I find playing 3. ... Nxe4 has Elo 2245 (until this Carlsen blitz game of course).
The sample size here is quite small, and maybe the highly-rated players have avoided 3. ... Nxe4 just because they are worried about stepping in to a well-prepared trap, instead preferring to head for more familiar ground. Nevertheless, the fact that the strongest players consistently avoid accepting the gambit - except for Carlsen, who got stomped, though it's just a blitz game - has made me curious:
What is the the theoretical status of the Roscher Gambit? Or is it too seldom played to even have a theoretical status?
And if it's the case that
3. ... Nxe4isn't simply good for Black, then why doesn't the Roscher appear more often, or at least have the same popularity among amateurs as something like, say, the Blackmar-Diemer Gambit?
I had no luck finding any prose account of the gambit by a strong player, and would appreciate any pointers to such.
3... c5with probable transposition to a Sicilian, although I guess White has the potential to play something offbeat like4. dxc5. This gambit bears some resemblance to something called the Omega Gambit, which can arise by an Alekhine Defense move order via1. e4 Nf6 2. d4, or via1. d4 Nf6 2. e4. – Greg E. Jul 09 '12 at 14:283. ... Nxe4. For 2200+ players, there were 2, both drawn. It's pretty clear the accepted gambit is not well liked by masters. c5 e5 and Nc6 were black's more typical 3rd move responses, with c5 giving black the best result. c5 is played as often as all other responses combined. EDIT - chesstempo has 7,000-ish master games featuring3. Nf3– Tony Ennis Jul 09 '12 at 15:121. e4 d6 2. d4 Nf6 3. Nf3, rather than 7,000-ish. Once you're at that position in chesstempo's game explorer, it indicates 5,484 games for3. ... c5, but I think that's with it handling transpositions; i.e. it's indicating that many games in the database which ended up in the position after3. ... c5via all move orders combined. If you go to the position after1. e4 d6 2. d4 Nf6, the explorer indicates only 30 games reaching the position after3. Nf3. – ETD Jul 09 '12 at 15:283. Nf3is played. – Tony Ennis Jul 09 '12 at 15:40Gambit (I don't know the name of the gambit). I remember looking it up in another database, and there were more games, but I looked it up onchesstempofound one rapid game between two 2200+ players and white played2.e4'. A possible explanation is error in the database, the moves got somehow entered in the wrong order, and that's all there is to it. However, it is probably not the case. – Akavall Jul 09 '12 at 18:151. e4 d6 2. d4 Nf6 3. Nf3 Nxe4 4. c4 e6 5. Bd3 Nf6 6. Nc3 Be7 7. O-O O-O 8. Re1 c5 9. dxc5 dxc5 10. Ne5 Nfd7 11. Nxd7 Qxd7 12. Bf4 Nc6 13. Qf3 f5 14. Rad1 Nd4 15. Qe3 b6 16. Be5 Ba6 17. Bf1 Bf6 18. Ne2 Bxe5 19. Qxe5 Nc6 20. Qxf5 exf5 21. Rxd7 Rfd8 22. Rxd8+ Rxd8 23. Nc3 Kf8 24. Rd1 Rxd1 25. Nxd1 g5– Tony Ennis Jul 09 '12 at 23:00
– Tony Ennis Jul 10 '12 at 06:1026. Bd3 h6 27. g3 Nb4 28. Bxf5 Bxc4 29. a3 Nd5 30. Be4 Ke7 31. Bxd5 Bxd5 32. f4 Ke6 33. Kf2 gxf4 34. gxf4 Bc6 35. Ke3 h5 36. Nf2 Kf5 37. Nd3 Be4 38. Ne5 Bd5 39. Nd3 Ba2 40. Ne5 Bd5 41. Nd7 Ke6 42. Ne5 Bg2 43. Nd3 Bb7 44. Ne5 Bg2 45. Nd3 Bb7 46. Ne5 Bg2 47. Nd3 Bc6 48. Ne5looking like 1/2-1/217. Bf1and not17. Nb5? – user21820 Aug 12 '21 at 04:20