Ideas Behind The Jobava-Prié (part five)

WHITE has a radically sharper, but little-known way, of meeting 3...c5 (after 1.d4 d5 2.Nc3 Nf6 3.Bf4) that is reminiscent of the Albin Countergambit, but with colours reversed.
There are just 11 examples of 4.e4!? in ChessBase's 2020 Mega database, compared with 368 for 4.e3, but five of the 11 outings are by players rated well over 2500, and the move could easily pack a surprise punch at club level.
Kirill Alekseenko (GM 2563) - Sergei Rublevsky (GM 2683)
Russian Rapid Championship (Sochi) 2017

Position after 4.e4!?

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4...Nxe4
This variation is in its infancy and there is no consensus as to how Black should react.
Nils Grandelius (GM 2643) - Pia Cramling (GM 2453), EU Blitz Championship (Tallinn, Estonia) 2016, saw 4...dxe4 5.dxc5 Qa5 6.Bb5+ Bd7 7.Qe2 a6 8.Bc4 Nc6 9.0-0-0 Qxc5 10.Nxe4 Nxe4 11.Qxe4 with an unclear position (1-0, 41 moves).
Black went wrong immediately in Boris Grachev (GM 2626) - Dmity Kryakvin (GM 2595), Russian Blitz Championship (Sochi) 2018, with 4...Nc6?, when the thematic 5.Nb5 would have been embarrassing. White whiffed with 5.Bb5+?, and the game was eventually drawn.
The only other known move, apart from the text, is 4...cxd4, which was played by an 1871 in 2019. After 5.Qxd4 Nc6 6.Bb5 Bd7 7.Bxc6 Bxc6 8.e5 Ne4!? 9.e6!? the position was unclear.
Clearly there is a lot to be discovered in these lines.
5.Nxe4 dxe4 6.dxc5 Qa5+ 7.c3 Qxc5 8.Qa4+ Nc6 9.Qxe4 g6
Olexandr Bortnyk (GM 2579) - Alexander Grischuk (GM 2747), ICC Blitz Final 2016, continued 9...Bf5 10.Qe3?! (Stockfish10 and Komodo10 prefer 10.Qa4, so 10...e5 can be met by 11.Be3) e5 11.Qxc5 Bxc5 12.Bg3 0-0-0, when Black had a large lead in development (0-1, 44 moves).
10.Qc4 Qa5 11.Qb5 Bg7 12.Qxa5 Nxa5 13.Bb5+ Nc6 14.0-0-0 Be6 15.Kb1 a6 16.Bxc6?!
Giving up the bishop-pair on a fairly open board with rival pawn-majorities and the possibility of opposite-side castling must be questionable. The engines reckon White should retreat the bishop to a4, d3 or even e2.
16...bxc6 17.Nf3 0-0 18.Be5 Bh6 19.Nd4 Bd5 20.f3 f6 21.Bg3 e5 22.Nc2 a5 23.Rhe1 Rfd8 24.b3 a4 25.Kb2 c5?!
Black is much better after 25...Be6, or 25...axb3 26.axb3 Be6, according to the engines.
26.c4 axb3 27.axb3 Be6 28.Kc3?
Black's advantage is smaller after 28.Rxd8+ Rxd8 29.Re2, according to the engines.
28...Bf5 29.Bh4
Or 29.Rxd8+ Rxd8 30.Re2 Bc1 (threatens 31...Rd3#) 31.Ne1 Ba3 32.Bf2 g5 (creating a retreat square for the f5 bishop) 33.g4 Bg6 34.h4 gxh4 35.Bxh4 Rd1 36.Re3 (White is almost in zugzwang) Bb4+ 37.Kb2 Kf7, and Black improves his position at his leisure (the engines have Black the equivalent of well over a rook ahead).
Perhaps best is the engines' 29.b4 Rxd1 30.Rxd1, but Black invades and wins a pawn with 30...Ra2 31.Ne1 Ra3+ 32.Kb2 cxb4 33.Nc2 Rc3 34.Nxb4 Rxc4.
29...Rxd1 30.Rxd1 Ra2 31.Ne1 Be3 32.b4
Best, according to the engines, but Black can now wrap matters up with 32...Bd4+. Rublevsky played 32...g5 33.Kb3 Re2 34.Bg3 cxb4 35.Kxb4 Bd4 and won anyway in 56 moves - the bishops were just too strong.