[Comment "auto-generated from http://www.jesseo.com/chesspublishing/pgn.php?pgndata=[Event%20%26quot;Analysis%26quot;]%0A[Site%20%26quot;Benoni%20Pirc%26quot;]%0A[Date%20%26quot;2015.01.01%26quot;]%0A[Round%20%26quot;%26quot;]%0A[White%20%26quot;9.f5%26quot;]%0A[Black%20%26quot;8...Rb8%20variation%26quot;]%0A[Result%20%26quot;*%26quot;]%0A[EventDate%20%26quot;2015.01.01%26quot;]%0A%0A1.e4%20d6%202.d4%20Nf6%203.Nc3%20g6%204.f4%20Bg7%205.Nf3%20O-O%206.Bd3%20Na6%207.O-O%20c5%208.d5%20Rb8%209.f5%20gxf5%2010.exf5%20%26%23123;This%20is%20best.%26%23125;%2010...Nc7%20%26%23123;Also%20best,%20although%2010...b5%20looks%20more%20or%20less%20playable.%26%23125;%2011.Ng5%20%0A%26nbsp;%20%26nbsp;%20(%2011.Qe1%20b5%2012.Qh4%20%0A%26nbsp;%20%26nbsp;%26nbsp;%20%26nbsp;%26nbsp;%20(%2012.Qg3%20c4%2013.Nd4%20Kh8%2014.Nc6%20Qe8%2015.Be2%20Rb6%20%26%23123;Unclear.%26%23125;%20)%0A%26nbsp;%20%26nbsp;%26nbsp;%20%26nbsp;%26nbsp;%20(%2012.Ng5%20c4%2013.Be2%20Bd7%2014.Qh4%20Qc8%20%26%23123;Black%20is%20slightly%20better.%20Black%20will%20bring%20in%20extra%20defence%20via%20f5.%26%23125;%20)%0A%26nbsp;%20%26nbsp;%2012...c4%2013.Be2%20Bb7!?%2014.a4%20b4%2015.Ne4%20Nxe4%2016.Qxe4%20Bxd5%20%26%23123;Unclear.%20Black%20does%20not%20look%20worse,%20even%20though%20white%20may%20regain%20his%20pawn.%26%23125;%20)%0A11...b5%2012.Nge4%20Nxe4%20%26%23123;Best%20even%20though%20it%20looks%20strange%20to%20exchange%20this%20well%20entrenched%20knight.%26%23125;%2013.Nxe4%20%0A%26nbsp;%20%26nbsp;%20(%2013.Bxe4%20Ne8%2014.Bd3%20c4%2015.Be2%20Nf6%20%26%23123;Looks%20OK%20for%20black.%26%23125;%20)%0A13...c4%2014.f6!%20%26%23123;This%20is%20the%20point%20behind%20white%27s%20play.%20He%20has%20gained%20a%20chance%20to%20secure%20a%20structural%20advantage.%26%23125;%2014...exf6%2015.Be2%20f5%20%26%23123;I%20don%27t%20think%20alternatives%20here%20are%20better.%20Black%20should%20use%20this%20pawn%20while%20it%20is%20still%20alive.%26%23125;%2016.Ng3%20Re8%2017.a4%20%26%23123;White%20probably%20needs%20to%20try%20this.%20If%20he%20can%20weaken%20black%27s%20structure%20enough%20the%20position%20may%20in%20the%20long%20run%20become%20favorable.%26%23125;%20%0A%26nbsp;%20%26nbsp;%20(%2017.Nxf5%20Bxf5%2018.Rxf5%20Qe7%2019.Bh5%20Qe1+%20%26%23123;Should%20be%20OK%20for%20black.%26%23125;%20)%0A17...a6%20%26%23123;I%20think%20this%20is%20best%20although%20there%20are%20a%20few%20interesting%20alternatives.%20White%27s%20play%20has%20almost%20been%20forced%20untill%20now%20but%20here%20he%20has%20a%20few%20alternatives.%26%23125;%2018.Nxf5%20%26%23123;Simplest%20and%20not%20such%20a%20bad%20try%20for%20an%20edge.%26%23125;%20%0A%26nbsp;%20%26nbsp;%20(%2018.c3!?%20%26%23123;More%20complicated.%26%23125;%2018...Be5%2019.axb5%20%0A%26nbsp;%20%26nbsp;%26nbsp;%20%26nbsp;%26nbsp;%20(%2019.Nxf5%20Bxf5%2020.Rxf5%20Qh4%2021.g3%20Qe4%2022.Rf2%20Qxd5%2023.Bd2%20f6%20%26%23123;With%20compensation%20but%20probably%20not%20more.%26%23125;%20)%0A%26nbsp;%20%26nbsp;%2019...Qh4%2020.b6%20f4%20%26%23123;With%20some%20counter%20chances.%20One%20line%20now%20is:%26%23125;%2021.Bxf4%20Bxf4%2022.bxc7%20Rxb2%2023.Bh5%20Bxg3%2024.Bxf7+%20Kg7%2025.hxg3%20Qe4%2026.Rf3%20Qe2%2027.Qf1%20Qxf1+%2028.Kxf1%20Ree2!%20%26%23123;Equal.%20With%20a%20perpetual%20check%20mechanism.%26%23125;%20)%0A%26nbsp;%20%26nbsp;%20(%2018.axb5%20axb5%2019.Nxf5%20%0A%26nbsp;%20%26nbsp;%26nbsp;%20%26nbsp;%26nbsp;%20(%2019.c3%20Re5%2020.Bf3%20Na6%20%26%23123;Unclear.%20Black%20may%20sacrifice%20an%20exchange%20on%20e5%20to%20plant%20a%20knight%20on%20d3.%26%23125;%20)%0A%26nbsp;%20%26nbsp;%2019...Bxf5%2020.Rxf5%20Re5%2021.Rxe5%20Bxe5%2022.g3%20Ra8%2023.Rxa8%20Qxa8%2024.Bf3%20Qa1%2025.b3%20cxb3%2026.cxb3%20Nxd5%2027.Bxd5%20Bb2%20%26%23123;Equal.%26%23125;%20)%0A18...Bxf5%2019.Rxf5%20Qe7%2020.Bh5%20%0A%26nbsp;%20%26nbsp;%20(%2020.Bf1%20Qe4%2021.Qh5%20Qxc2%2022.Bf4%20Qxb2%2023.Qxf7+%20Kh8%2024.Rd1%20bxa4%2025.Qxc7%20Rbc8%2026.Qd7%20a3%2027.Rf7%20Rcd8%20%26%23123;Unclear.%20Is%20probably%20OK%20for%20black.%26%23125;%20)%0A20...Qe1+%2021.Rf1%20%0A%26nbsp;%20%26nbsp;%20(%2021.Qxe1%20Rxe1+%2022.Kf2%20Rxc1%2023.Rxc1%20Bxb2%20%26%23123;Unclear.%20Looks%20like%20a%20nice%20exchange%20sacrifice.%20Note%20that%20the%20a-pawn%20will%20become%20dangerous.%26%23125;%20)%0A21...Qxd1%2022.Rxd1%20a5%20%26%23123;Perhaps%20white%20can%20claim%20a%20tiny%20edge.%20Black%20looks%20quite%20OK%20though.%26%23125;%20*"]
[Event "Analysis"]
[Site "Benoni Pirc"]
[Date "2015.01.01"]
[Round ""]
[White "9.f5"]
[Black "8...Rb8 variation"]
[Result "*"]
[EventDate "2015.01.01"]

1.e4 d6 2.d4 Nf6 3.Nc3 g6 4.f4 Bg7 5.Nf3 O-O 6.Bd3 Na6 7.O-O c5 8.d5 Rb8 9.f5 gxf5 10.exf5 {This is best.} 10...Nc7 {Also best, although 10...b5 looks more or less playable.} 11.Ng5 
    ( 11.Qe1 b5 12.Qh4 
        ( 12.Qg3 c4 13.Nd4 Kh8 14.Nc6 Qe8 15.Be2 Rb6 {Unclear.} )
        ( 12.Ng5 c4 13.Be2 Bd7 14.Qh4 Qc8 {Black is slightly better. Black will bring in extra defence via f5.} )
    12...c4 13.Be2 Bb7!? 14.a4 b4 15.Ne4 Nxe4 16.Qxe4 Bxd5 {Unclear. Black does not look worse, even though white may regain his pawn.} )
11...b5 12.Nge4 Nxe4 {Best even though it looks strange to exchange this well entrenched knight.} 13.Nxe4 
    ( 13.Bxe4 Ne8 14.Bd3 c4 15.Be2 Nf6 {Looks OK for black.} )
13...c4 14.f6! {This is the point behind white's play. He has gained a chance to secure a structural advantage.} 14...exf6 15.Be2 f5 {I don't think alternatives here are better. Black should use this pawn while it is still alive.} 16.Ng3 Re8 17.a4 {White probably needs to try this. If he can weaken black's structure enough the position may in the long run become favorable.} 
    ( 17.Nxf5 Bxf5 18.Rxf5 Qe7 19.Bh5 Qe1+ {Should be OK for black.} )
17...a6 {I think this is best although there are a few interesting alternatives. White's play has almost been forced untill now but here he has a few alternatives.} 18.Nxf5 {Simplest and not such a bad try for an edge.} 
    ( 18.c3!? {More complicated.} 18...Be5 19.axb5 
        ( 19.Nxf5 Bxf5 20.Rxf5 Qh4 21.g3 Qe4 22.Rf2 Qxd5 23.Bd2 f6 {With compensation but probably not more.} )
    19...Qh4 20.b6 f4 {With some counter chances. One line now is:} 21.Bxf4 Bxf4 22.bxc7 Rxb2 23.Bh5 Bxg3 24.Bxf7+ Kg7 25.hxg3 Qe4 26.Rf3 Qe2 27.Qf1 Qxf1+ 28.Kxf1 Ree2! {Equal. With a perpetual check mechanism.} )
    ( 18.axb5 axb5 19.Nxf5 
        ( 19.c3 Re5 20.Bf3 Na6 {Unclear. Black may sacrifice an exchange on e5 to plant a knight on d3.} )
    19...Bxf5 20.Rxf5 Re5 21.Rxe5 Bxe5 22.g3 Ra8 23.Rxa8 Qxa8 24.Bf3 Qa1 25.b3 cxb3 26.cxb3 Nxd5 27.Bxd5 Bb2 {Equal.} )
18...Bxf5 19.Rxf5 Qe7 20.Bh5 
    ( 20.Bf1 Qe4 21.Qh5 Qxc2 22.Bf4 Qxb2 23.Qxf7+ Kh8 24.Rd1 bxa4 25.Qxc7 Rbc8 26.Qd7 a3 27.Rf7 Rcd8 {Unclear. Is probably OK for black.} )
20...Qe1+ 21.Rf1 
    ( 21.Qxe1 Rxe1+ 22.Kf2 Rxc1 23.Rxc1 Bxb2 {Unclear. Looks like a nice exchange sacrifice. Note that the a-pawn will become dangerous.} )
21...Qxd1 22.Rxd1 a5 {Perhaps white can claim a tiny edge. Black looks quite OK though.} *