[Comment "auto-generated from "]
[Event "Byrne with 4...c6 analysis"]
[Site "Chesspub"]
[Date "2016.01.01"]
[Round "?"]
[White "5.Qd2 and 6.f4"]
[Black "5...Nbd7 with 6...d5"]
[Result "*"]
[EventDate "2016.01.01"]

1.e4 d6 2.d4 Nf6 3.Nc3 g6 4.Bg5 c6 5.Qd2 Nbd7 6.f4 d5!? 7.e5 Ne4 8.Nxe4 dxe4 9.Bc4 
    ( 9.Nh3 f6 10.Bh4 Bh6 
        ( 10...Nb6!? 11.Nf2 Bf5 
            ( 11...Bh6 12.exf6 Nd5 13.Nxe4 Bxf4 14.Qf2 Bf5 15.Bd3 )
            ( 12.c4!? h5 13.Qe3!? Na4 
                ( 13...fxe5 14.dxe5 Na4 15.b3 Qa5+ 16.Qd2 Qxd2+ 17.Kxd2 {(+=) Black is somewhat worse, though there are likely possibilities to simplify and try to hold.} )
            14.b3 Qa5+ 15.Qd2 Qxd2+ 16.Kxd2 Bh6 17.bxa4 Bxf4+ 18.Ke1 fxe5 19.dxe5 Bxe5 20.Rc1 Bb2 21.Rc2 
                ( 21.Bg5 e3 22.Bxe3 Bxc1 23.Bxc1 O-O-O {(=) White will not be able to put black under pressure.} )
            21...Bd4 22.Nd1 e3 23.Rc1 O-O-O 24.Bg5 Bb6!? 25.Nxe3 Ba5+ 26.Ke2 
                ( 26.Kf2 Rhf8 27.Bxe7 Bg4+ 28.Bxf8 Rxf8+ 29.Kg3 Bc7+ 30.Kh4 Bd8+ 31.Kg3 Bc7+ 32.Kh4 Bd8+ 33.Kg3 Bc7+ {(=)} )
            26...Rd2+ 27.Kf3 Be6 28.Ke4 Rhd8 29.Ke5 Bd7!? {(∞) to (+=)} )
        12...Nd5 13.f7+ Kxf7 14.Bc4 Ke8 15.Nd1 Bg7 16.c3 Bf6 17.Bf2 {(+=) Black has taken structural degradation without obviously achieving enough for it.} )
    11.Nf2 Nxe5 
        ( 11...fxe5 12.dxe5 Rf8 13.g3 {(+=)} )
    12.Nxe4 Bf5 
        ( 12...Nf7 13.Bc4 Bf5 14.Ng3 Nd6 15.Bb3 Qc7 16.O-O {(+=)} )
        ( 13.Ng3 Be6!? 14.Qe3 
            ( 14.dxe5 Qxd2+ 15.Kxd2 g5 
                ( 15...O-O-O+ 16.Bd3!? Bxf4+!? 17.Ke1 Bxe5 {(∞)} )
            16.Bxg5 O-O-O+ 17.Bd3 fxg5 18.f5 g4+ {(∞) With decent compensation.} )
        14...Qb6 15.Be2 Bd5 16.O-O Nc4 17.Bxc4 Bxc4 18.Rfe1 O-O-O! 19.b3 Qxd4 20.Qxd4 Rxd4 21.bxc4 Bxf4 22.Rad1 Rhd8 23.Rxd4 Rxd4 {(∞)} )
        ( 13...Qb6? 14.Nxf6+ exf6 15.Bxf6 O-O 16.Bxe5 {(+/ - )} )
    14.Nxf6+ Nxf6 15.Bxf6 Bxf4 16.Qxf4 Qa5+!? 
        ( 16...exf6 17.O-O-O Qd5 18.Bd3 O-O-O 19.Bxf5+ gxf5 {(=) to (+=)} )
    17.c3 exf6 18.Bc4 
        ( 18.g4 Qd5 {(∞)} )
    18...O-O-O 19.O-O Qc7 20.Qf2 Rhe8 {Black is OK.} )
    ( 9.Ne2 {Is probably the most critical move.} )
9...Nb6 10.Bb3 a5 11.a4 
    ( 11.a3 a4 12.Ba2 h6!? {A reason not to prefer an earlier f6.} 13.Bh4 Nd5 14.Bf2 b5 15.Ne2 f5 {(=) Black is well placed to meet pawn moves on both sides of the board and should be fine.} )
11...f6 12.Bh4 
    ( 12.exf6 exf6 13.Bh4 Nd5 14.Ne2 Bb4!? 15.c3 Be7 {(=+) Black will get a stable and mildly promising position after f5.} )
12...Bh6 13.exf6 exf6 14.Ne2 Qe7 15.d5!? 
    ( 15.O-O Be6 16.Qe3 
        ( 16.Nc3 Bxb3 17.Nxe4 Qxe4 18.Rae1 Bd5 19.Rxe4+ Bxe4 20.Qe3 f5 21.Qa3 Nd5 22.Qd6 Bxc2 23.Re1+ Be4 24.Qe6+ Kf8 25.Qd6+ Kg8 26.Qe6+ Kf8 27.Qd6+ Kg8 28.Qe6+ Kf8 {(=) Draw.} )
        ( 16.Ng3 Bxb3 17.cxb3? e3 18.Qd3 Nd5 19.Rae1 Bxf4 {( - +)} )
    16...Bd5 17.Nc3 
        ( 17.Bxd5 cxd5 18.Qb3 Qd6 19.Qb5+ Kf7 20.f5 g5 21.Bg3 Qc6 22.Nc3 Bf8 23.Qe2 h5 {(=) Seems roughly equal.} )
    17...Qe6 18.Bxd5 cxd5 19.Nb5 Qc6 20.b3 
        ( 20.Qa3 Bf8 21.Qa2 f5 22.b3 Bg7 23.Qa3 Bf8 24.Qc1 Bg7 25.Qa3 Bf8 26.Qc1 Bg7 27.Qa3 {(=) Draw.} )
    20...O-O 21.Rac1 Qd7 22.c4 f5 23.Qe2 
        ( 23.c5?! Nc8 24.Be1 Na7 25.Nxa7 Rxa7 26.Bc3 Rb8 27.Rf2 b6 {( - /+)} )
    23...Bg7 24.Bf2 Rf6 25.Rc2 Rc6 26.Be3 Bf8 {(=)} )
    ( 15.c4 O-O 16.Bf2 
        ( 16.O-O Be6 17.Qc3 Qb4 18.Rfc1 Qxc3 19.Rxc3 f5 {(=) to (=+)} )
    16...Nd7 17.h4!? Rd8 18.c5+ Kh8 19.Qc3 b6 {With counterplay.} )
15...Nxd5 16.Bxd5 cxd5 17.Qxd5 Be6 18.Qxe4 {Black has reasonable compensation. Possible line:} 18...Kf7 19.O-O Rhe8 20.Rfe1 Qb4 21.Nd4 f5 22.c3 fxe4 23.cxb4 Bc4 24.Nb5 Bxb5 25.axb5 axb4 26.Rxa8 Rxa8 27.Rxe4 Bf8 28.Bf2 Ra1+ 29.Re1 Ra5 30.Rd1 Ke6 31.Bd4 Rxb5 {(=) Black is fine.} *