**Ok I did a little research, and I got this conclusion:**After 13.a3 a5 white has 4 options:

1) 14.Nd5 transposing to a variation of the normal 13.Nd5. (It could be the most challenging maybe after all.)

2) 14.e5

3) 14.Rhe1

4) 14.Kb1 the debated one could follow 14...b4 15.axb4 axb4 16.Na2 and here:

4.1) 16...Be6 suggested before.

4.2) 16...Ra8 mentioned by me before after 17.Qxb4 turns complicated. Hopefully black will get compensation.

4.3) 16...Qc7

4.4) 16...Qa5

**Well what can I say?. Still, there is room for investigation I guess.**[Event "?"]

[Site "?"]

[Date "????.??.??"]

[Round "?"]

[White "New game"]

[Black "?"]

[Result "*"]

[PlyCount "52"]

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 g6 6. Be3 Bg7 7. f3 O-O 8. Qd2

Nc6 9. Bc4 Bd7 10. Bb3 Rc8 11. O-O-O Nxd4 12. Bxd4 b5 13. a3 {

not mentioned in any of my books and discs} a5 14. Kb1 {this position is

considred by Dearing in Play the Sicilian Dragon via a Kb1 move order.

Rogozenko only mentioen that black get good play in this position but does not

give any lines} (14. Nd5 {0-1 Ulker,A-Bayram,Y/Ankara 2007 (26)}) (14. e5 {

1/2-1/2 Vandevoort,P-Ahn,M/Belgium 2005 (17)}) (14. Rhe1 {

1/2-1/2 Pineda,J-Berza,I/ICCF 2008 (42)}) 14... b4 (14... Rb8 $2 15. e5) (14...

Re8 $6 {Ein uberflussiger Zug. In manchen Varianten nimmt der Turm nun dem Sf6

das Feld e8. Auserdem ist f7 nun nicht mehr so gut uberdeckt.} 15. h4 b4 16.

axb4 axb4 17. Na2 ({Nach} 17. Nd5 Nxd5 18. Bxg7 Kxg7 {

droht Schwarz stark 19...Da5 und 20...Ta8, z.B.} 19. Qxd5 (19. Bxd5 $2 Qa5)

19... Rc5 $1 20. Qxf7+ Kh8 21. Qf4 Qa5 22. Bd5 Rc7 $40) 17... Qa5 (17... Be6 $5

) 18. Qxb4 Qa8 (18... Qa6 $5) (18... Ra8 $5) 19. e5 Rb8 20. Qa3 ({Nicht} 20.

Qd2 $2 dxe5 21. Bxe5 $2 Rxb3 $1 22. cxb3 Bf5+ 23. Ka1 (23. Kc1 Rc8+ 24. Nc3 (

24. Bc3 Qxa2 $19) 24... Qa1#) 23... Qxa2+ 24. Kxa2 Ra8+ 25. Qa5 Rxa5#) 20...

Qxa3 21. bxa3 dxe5 22. Bxe5 Rb7 (22... Ra8 $4 23. Bxf6 $18) 23. Nb4 $16 {

Das Hauptsorgenkind des Schwarzen ist der in der Luft hangende Ld7.} Ra8 24.

Bb2 Rba7 25. Rhe1 Rxa3 $5 {

Durch diese Gewaltaktion mochte Schwarz den Lg7 zum Leben erwecken.} (25... e6

$16) 26. Bxa3 Rxa3 27. Kb2 Ra8 28. c3 {Weis mus nun noch einige kleine

Gemeinheiten beachten, bis sich schlieslich der Materialvorteil durchsetzt.} (

28. Rxe7 $2 Nd5+) 28... e6 29. Ra1 Rc8 30. Ra7 Nd5 31. Nxd5 exd5 32. Rd1 (32.

Rc1 Be6 33. Ra5 $2 (33. Ra6 $142) 33... d4 $132) 32... Bxc3+ 33. Ka3 Be6 34.

Bxd5 Bxd5 35. Rxd5 $18 Rc6 36. h5 gxh5 37. Rxh5 h6 38. Kb3 Kg7 39. Ra4 Bf6 40.

Rg4+ Kh7 41. Rf5 Kh8 42. Kb4 Kh7 43. Kb5 Rd6 44. Kc4 Ra6 45. Kd3 Ra3+ 46. Ke2

Ra6 47. Kf2 Rb6 48. Kg3 Ra6 49. Kh3 Rb6 50. Ra5 Rb7 51. Ra6 Bg7 52. Rf4 Rc7 53.

Rf5 Rb7 54. Kg4 Rc7 55. f4 Rb7 56. g3 Rc7 57. Rfa5 Rc4 58. Rd5 Rc7 59. Rad6 Rc4

60. Kh5 Rc3 61. Rd3 Rc5+ 62. R6d5 Rc6 63. Rd7 Kg8 64. R3d6 Rc3 65. Kg4 Rc4 66.

Ra6 Rc5 67. Ra8+ {1-0 Timoshenko,G-Shahade,G/New York 1999/[Schulz,A] (67)}) (

14... Rb8 {'?' Schulz,A.} 15. e5 (15. Ne2 b4 16. axb4 axb4 17. e5 Qa5 18. Qe3

Ra8 19. Kc1 dxe5 20. Qxe5 Bh6+ 21. f4 Qxe5 22. Bxe5 Ne4 23. c3 Bg4 24. Rhe1 Nc5

25. Bd5 Ra1+ 26. Kd2 Rxd1+ 27. Rxd1 bxc3+ 28. bxc3 e6 29. Bf3 Bxf3 30. gxf3

Rd8+ 31. Ke1 Rxd1+ 32. Kxd1 Bg7 33. Nc1 f6 34. Bd4 Nd7 35. Kc2 e5 36. fxe5 fxe5

37. Be3 Kf7 38. Nb3 Ke6 39. Kd3 Bf8 40. Kc4 Bd6 {

0-1 Aliev,E-Abdulov,O/Baku 2003 (40)}) 15... Ne8 16. exd6 Nxd6 17. Bxg7 Kxg7

18. Rhe1 Bc6 19. Bd5 Bxd5 20. Nxd5 e5 21. Ne3 Nb7 22. Qc3 Qe8 23. f4 f6 24.

fxe5 fxe5 25. Ng4 Rc8 26. Qxe5+ Qxe5 27. Rd7+ Rf7 28. Rxf7+ Kxf7 29. Nxe5+ Kf6

30. Nd7+ Kf7 31. Re5 Nd6 32. b3 a4 33. Kb2 axb3 34. cxb3 Rd8 35. Nc5 Nf5 36.

Kc3 Rd1 37. Nd3 Nd6 38. a4 bxa4 39. bxa4 Ra1 40. a5 Ra3+ 41. Kd4 Nf5+ 42. Kc4

Nd6+ 43. Kd4 Nf5+ {1/2-1/2 Sanz Alonso,F-Kopczynski,M/Warsaw POL 2008 (43)})

15. axb4 axb4 16. Na2 Qa5 {is only move mentioend by Dearing} (16... Be6 {

is a Rybka 3 suggestion and suggested by Shultz in an annotatiion of a game

'!?' '!?'} 17. Bxe6 fxe6 18. Qxb4 {

black wants to exchange darksquaered Bishops to get a grip at the f4 square}

Nh5 (18... Rb8 19. Qc4 Qd7 20. Nb4 {is good for white} Rfc8 21. Qb3 Nh5 22.

Rhe1) (18... Ra8 19. Rd3 (19. Qc4 Qd7 20. Nb4 Rfc8 21. Qb3 Nxe4 22. Bxg7 Nc5

23. Qc3 Na6 24. Qb3 Nxb4 25. Qxb4 Kxg7 26. Qd4+ Kg8) 19... Nh5 20. Bxg7 Kxg7

21. Ra3 (21. g3 e5 22. Re1 Qc7 23. Ra3 Rab8 24. Qd2 Rb7 25. Nc3 Nf6) 21... e5)

19. Bxg7 (19. c3 Ra8 20. Bxg7 Kxg7 21. Qc4 e5 22. Nb4 Qd7 23. Nd5 Qa7 24. Qc7

Qa2+ 25. Kc2 Rab8 26. Nb4 Qf7 27. Nd5 Rfe8 {unclear}) 19... Kxg7) (16... Ra8

17. Qxb4 Qc8 {is an interesting line} 18. Rhe1 (18. e5 dxe5 19. Bxe5 Be6 20.

Rhe1 Qa6 21. Bxe6 fxe6 22. Qa3 Qxa3 23. bxa3 Rxa3 24. Nb4 Rc8 25. Rd4 Ra5 26.

Nd3 Ra7) 18... Be6 19. Bxe6 Qxe6 20. Qb3 Qd7 21. e5 dxe5 22. Bxe5 Qa7 {

black has compensation}) (16... Qc7 17. Nxb4 Ra8 18. Nd5 Nxd5 19. exd5 Bxd4 20.

Qxd4 Rfb8 21. g4 Qa5 22. Kc1 Rb4 23. Qe3 Qa1+ 24. Kd2 Qxb2 25. Rb1 Qf6 26. g5

Qf4 27. Qxf4 Rxf4 28. Ke3 Rh4 29. Kf2 Bf5 30. Kg3 Rb4 31. Ra1 Rxa1 32. Rxa1 Rb7

33. Kf2 Rc7 34. Ra2 e6 35. c4 Kf8 36. Ra8+ Ke7 37. Ba4 f6 38. gxf6+ Kxf6 39.

Bc6 Bd3 40. Ra4 g5 41. Ke3 Bc2 42. Rb4 exd5 43. Bxd5 Ke5 44. Rb8 Bg6 45. Rb5

Rc5 46. Rb7 Bf5 47. Re7+ Kf6 48. Rf7+ Ke5 49. Re7+ Kf6 {

1/2-1/2 Sulc,G-Solic,K/Djakovo 2006 (49)}) 17. Qxb4 {only move mentioned} (17.

Rhe1 {may be an improvment}) 17... Qa6 18. c4 (18. Qb6 {

is given as an improment} Qa8 19. Qa7 Qc6 {

analyse ends here without any assesments}) 18... Ra8 (18... Rb8 {

is Rybka preferences} 19. Qc3 Be6 {

black has enourmues preusure and Rybka calls it close to winning}) 19. Kc2 $2 (

19. Qc3 {is a better try but after} Rfb8 {black has all play}) 19... Rfb8 20.

Qc3 Rxb3 21. Qd2 Qxc4+ 22. Bc3 Rxa2 23. Rb1 Nxe4 24. fxe4 Qxe4+ 25. Kxb3 Be6+

26. Qd5 Qa4# {0-1 Baragano Campa,D-Mamedov,R/Aviles 2002 (26)} *

bragesjo wrote on 12/27/09 at 15:50:38:

Home agian a day earlyer than expected so I have an engine agian for a couple of days. The line you gave is almost unmentioend by any books or discs and I only found three games where one was irrelevent for white played Nd5 instead of Na2. Blacks score was two wins and one defeat but to few games to draw any conclusions.

[Event "?"]

[Site "?"]

[Date "????.??.??"]

[Round "?"]

[White "New game"]

[Black "?"]

[Result "*"]

[PlyCount "38"]

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 g6 6. Be3 Bg7 7. f3 O-O 8. Qd2

Nc6 9. Bc4 Bd7 10. Bb3 Rc8 11. O-O-O Nxd4 12. Bxd4 b5 13. a3 {not mentioned in

any of my books and discs} a5 14. Kb1 {this position is considred by Dearing

in Play the Sicilian Dragon via a Kb1 move order. Rogozenko only mentioen that

black get good play in this position but does not give any lines} b4 15. axb4

axb4 16. Na2 Qa5 {is only move mentioend by Dearing} (16... Be6 {is a Rybka 3

suggestion and suggested by Shultz in an annotatiion of a game} 17. Bxe6 fxe6

18. Qxb4 {black wants to exchange darksquaered Bishops to get a grip at the f4

square} Nh5 (18... Rb8 19. Qc4 Qd7 20. Nb4 {is good for white} Rfc8 21. Qb3 Nh5

22. Rhe1) (18... Ra8 19. Rd3 (19. Qc4 Qd7 20. Nb4 Rfc8 21. Qb3 Nxe4 22. Bxg7

Nc5 23. Qc3 Na6 24. Qb3 Nxb4 25. Qxb4 Kxg7 26. Qd4+ Kg8) 19... Nh5 20. Bxg7

Kxg7 21. Ra3 (21. g3 e5 22. Re1 Qc7 23. Ra3 Rab8 24. Qd2 Rb7 25. Nc3 Nf6) 21...

e5) 19. Bxg7 (19. c3 Ra8 20. Bxg7 Kxg7 21. Qc4 e5 22. Nb4 Qd7 23. Nd5 Qa7 24.

Qc7 Qa2+ 25. Kc2 Rab8 26. Nb4 Qf7 27. Nd5 Rfe8 {unclear}) 19... Kxg7) (16...

Ra8 17. Qxb4 Qc8 {is an interesting line} 18. Rhe1 (18. e5 dxe5 19. Bxe5 Be6

20. Rhe1 Qa6 21. Bxe6 fxe6 22. Qa3 Qxa3 23. bxa3 Rxa3 24. Nb4 Rc8 25. Rd4 Ra5

26. Nd3 Ra7) 18... Be6 19. Bxe6 Qxe6 20. Qb3 Qd7 21. e5 dxe5 22. Bxe5 Qa7 {

black has compensation}) 17. Qxb4 {only move mentioned} (17. Rhe1 {may be an

improvment}) 17... Qa6 18. c4 (18. Qb6 {is given as an improment} Qa8 19. Qa7

Qc6 {analyse ends here without any assesments}) 18... Ra8 (18... Rb8 {is Rybka

preferences} 19. Qc3 Be6 {black has enourmues preusure and Rybka calls it

close to winning}) 19. Kc2 $2 (19. Qc3 {is a better try but after} Rfb8 {black

has all play}) 19... Rfb8 {0-1 Baragano Campa - Mamedov 2002} *