An annoying move for a Petroff expert like Ippolito!

3... Nc6

3... Bb4!? was Marshall's preference but high-level players use a simple solution: 4. Nxe5 O-O (4... Qe7 5. Nd3 Bxc3 6. dxc3 Qxe4+ 7. Qe2) 5. Be2 Re8 6. Nd3 Bxc3 7. dxc3 Nxe4 8. Nf4! and White's two Bishops give him a slight but lasting edge.

4. Bb5

In another game at the same tournament, Ippolito had to face 4. a3!?

SOS #1 called this "The Gunsburg Variation" and showed it is a viable White move that does not surrender White's advantage.

4... d5

The prescribed response. Worth noting is that the Halloween-like anti-Glek idea 4... g6 5. Nxe5!? Nxe5 6. d4 Nc6 7. d5 may actually be effective here with the b4 square covered.

5. Bb5 d4

5... Nxe4 6. Nxe5 Qf6 7. Nd3! Nxc3 8. dxc3 Be6 9. Bf4

6. Ne2 Nxe4

6... Bd6 must be safer.

7. d3 Nf6 8. Nxe5 Qd5 9. Nxc6 bxc6 10. Bc4 (10. Ba4!?) 10... Qxg2 11. Rg1 Qh3

On 11... Qxh2 12. Bf4 Qh5 13. Nxd4 Qxd1+ 14. Rxd1 leaves White with the better structure and development, but that may have been preferable to the middlegame struggle that follows.

12. Nxd4 Bg4 13. f3 Qxh2 14. Be3 Bd7 15. f4! Nd5

15... Qh4+ 16. Bf2 Qxf4 17. Qe2+ is no better.

16. Qf3 Nxe3

16... Qh4+ 17. Bf2 Qe7+ 18. Kd2 may be just a touch better, but Black still has the much more insecure king in all of these lines.

17. Qxe3+ Kd8 18. Nf3 Bc5 (18... Qxc2 19. Ne5) 19. d4! ( Black was hoping for 19. Qxc5?! Re8+ 20. Kd1 Qe2+ 21. Kc1 Qxf3)

19... Qh3 20. O-O-O (20. dxc5?? Re8) 20... Bd6 21. Rxg7 Re8 22. Qb3 Bg4

Black's attempts at tactical counterplay have all failed, and now White detonates a powerful Exchange sacrifice to emphasize his positional dominance.

23. Rxg4! Qxg4 24. Ne5 Qxf4+

24... Bxe5?? 25. dxe5+

25. Kb1 Qe4 26. Bd3 Qd5 27. Bc4 Qe4 28. Nxf7+ Kd7 29. Ne5+ Rxe5 30. dxe5 Qxe5

Black appears to have survived, and a pawn to the good, but all hope is illusory for him. The opposite-colored Bishops make it impossible for Black to protect the light squares around his King and White's attack inevitably breaks through by a sort of "triangulation" strangulation.

31. Qh3+ Kd8 32. Rg1 Qc5 33. Rg8+ Bf8 34. Qd3+ Ke8 35. Qe4+ Kd8 36. Qf4 Kd7 37. Qf7+ Qe7 38. Qf5+ Ke8 39. Rg4 Qd7 40. Be6 Qd1+ 41. Ka2 Qd6 42. Qf7+ and a nice mate follows 42...Kd8 43.Rd4!, 1-0 Howell,D-Ippolito,D/King of Prussia USA 2007.

4... Nd4

a) 4... Bb4 is still quite viable and recommended by both Mihail Marin in "Beating the Open Games" and by Nigel Davies in "Play 1.e4 e5!"

b) 4... Bc5!? is an interesting idea, analyzed in detail by Mark Morss online in a "Hard Chess" column from May 1999.

5. Bc4!?

A move that is completely ignored by John Nunn in both NCO and his otherwise very useful "New Ideas in the Four Knights." Where it is not ignored, it is generally underestimated. Evans and Smith, for instance, call it "toothless" and "tame."

a) 5. O-O! is White's safest option, as I discuss in a piece titled "Sutovsky's Anti-Rubinstein 5.O-O!" -- but Black has counterplay with 5... c6 6. Ba4 Qa5! transposing to lines that can arise from 5.Ba4 below.

b) 5. Ba4 has long been considered the main line, but Najer has not had much success with it, e.g.: 5... Bc5 (5... c6!? is recommended by John Emms in "Play the Open Games as Black," when the critical test is 6. Nxe5 d5 7. d3 Bd6) 6. Nxe5 O-O 7. Nd3 Bb6 8. e5 Ne8 9. Nd5 d6 10. Ne3 c6 11. c3 Nf5 12. O-O Bc7! 13. f4 Nxe3 14. dxe3 dxe5 15. Nxe5 Bf5 16. Bc2 Qxd1 17. Bxd1 Nf6= and though White retains the pawn, it simply serves to cramp his position -- 1/ 2-1/2 Najer,E-Onischuk,A/Moscow2002.

c) 5. Nxd4 exd4 6. e5 dxc3 7. exf6 Qxf6 (7... cxd2+? 8. Bxd2 Qxf6 9. O-O Be7 10. Bc3) 8. dxc3 Qe5+ 9. Qe2 Qxe2+ 10. Bxe2 Bc5 11. O-O d6= is totally level and usually agreed drawn -- and one of the main arguments against the Rubinstein Variation if Black has to play for a win.

5... Nxf3+

The often-recommended "shortcut" line, which sidesteps the complicated gambit continuation at the cost of relative passivity. This game suggests that Black has to gambit a pawn with either 5... Bc5 or the newer 5...c6! if he wants to stay in the fight.

a) 5... Nxe4?! has been tried, including by Ippolito himself at an earlier World Open. But a close analysis suggests that White can retain a solid edge after the surprising 6. Nxd4!

(a) 6. Bxf7+?! Kxf7 7. Nxe4 (7. Nxe5+? Kg8 8. Nxe4 Qe7 9. O-O Qxe5 0-1 Nixon,P-Sundeen,D/East Lansing 1992 (65)) 7... d5 (7... Kg8!? may be even better after 8. Nxd4 exd4 9. O-O d5 10. Ng3 Bd6 11. d3 h5 12. Qf3 c6 13. h3 Qc7 14. Ne2 Bg4 15. hxg4 hxg4 16. Qxg4 Bh2+ 17. Kh1 Bg1+ 0-1 Novak,M-Moller,K/Svetla nad Sazavou 1998) (but not 7... Nxf3+? 8. Qxf3+ Kg8?? 9. Ng5 1-0 Jowett-McDonald/London 1885) 8. Nxd4 exd4! 9. Qf3+ Kg8 10. O-O h5! (10... dxe4?? 11. Qb3+ forces mate) 11. Ng3 Bg4 12. Qb3 h4 13. Nh1 h3! 14. g3 Be2 15. Re1 d3 16. cxd3 Bf3 17. d4 Qf6 18. Qe3 Bxh1 19. f3 (19. Kxh1 Re8!!) 19... Bg2 20. d3 Qxf3 21. Qe6+ Qf7 22. Bf4 c6 23. Qg4 Be7 24. Re2 Bf6 25. Be5 Bxe5 26. Rxe5 Rf8 27. Qe2 Rh6 0-1 Yee,P-Ippolito,D/Philadelphia 2000.

(b) 6. Nxe4?! d5 7. Bxd5 Qxd5 8. d3 f5 9. Ned2 Bd7 10. O-O O-O-O 11. Nxd4 exd4 Tashtanbekov,A-Koukov,V/Bratislava 1993 (66).

(c) 6. Nxe5 Nd6 (6... Qg5?! 7. Bxf7+!) 7. Bd3 g6 8. Qg4 Nc6 9. Nf3 Bg7 10. O-O O-O 11. b3 Ne8 12. Bb2 d6 13. Qf4 Ne5 14. Be2 c6 15. d4 Nxf3+ 16. Bxf3 Nc7 17. Qd2 d5 18. Ne2 Re8= Malisauskas,V-Sulskis,S/Kaunas 2001 (77).

6... exd4?! (better 6... Nxc3 7. dxc3 exd4 8. O-O! (8. Qxd4 c6 9. Be3 d5 10. O-O-O Be6 11. Bb3) 8... d5 9. Re1+ Be6 10. Qh5 Qd7 (10... dxc4 11. Rxe6+ Be7 12. Re4! O-O 13. Rxd4) 11. Bxd5 O-O-O 12. Bxe6 fxe6 13. Qe5!) 7. Bxf7+! (7. Nxe4?! d5 8. Qe2 dxe4 9. Qxe4+ Qe7=) 7... Kxf7 8. Qh5+ g6 9. Qd5+ Kg7 10. Nxe4

b) 5... d6 is the best of Black's "safe" responses, though he still must face a sharp struggle after 6. Ng5!? d5 (6... Ne6 7. d4 Nxg5 8. Bxg5 Be7 9. O-O O-O 10. Qd3 Panov - Yudovich, USSR 1936) 7. exd5 h6 8. Nf3 Bg4 9. Be2 Nxe2 ( Another idea may be 9... Bf5!? 10. d3 Nxd5 with the idea of ...Nb4) 10. Qxe2 Bd6 11. h3 Bh5 12. d3 O-O 13. g4 Bg6 14. g5! ( necessary, as Black does well after 14. Bd2 e4!) 14... Nh5 Black has c ounterplay due to the Nf4 idea, and what follows is a very sharp and double-edged struggle: 15. Ne4!? (15. gxh6 Re8!?) 15... f5!? 16. gxf6 (16. Nxd6!?) 16... Bxe4! 17. Qxe4!? (17. dxe4 Qxf6 18. Nh2 Nf4 19. Ng4! looks better) 17... Qxf6 18. Ke2 Bc5 19. Rg1 Rae8 20. Rg6 Qf5 21. Be3 Bxe3 (21... Nf4+ 22. Bxf4 exf4 23. Re6 Qh5 24. Rg1) 22. fxe3 Qxh3 23. Rag1 Re7 24. Rxh6 Ng3+ 25. Rxg3 Qxg3 26. Qh7+ Kf7 27. e4 Qg4 28. Rh2 Qg6?? (28... Ke8 29. Qh5+ Qxh5 30. Rxh5 Ref7 31. Rxe5+ Kd7 32. Nd4 is a complicated ending) 29. Nxe5+! Rxe5 30. Rf2+ Qf6 31. Rxf6+ Kxf6 32. Qh2 Rfe8 33. c4 g6 34. c5 b6 35. b4 bxc5 1-0 Najer,E-Mastrovasilis,D/Dresden 2007.

c) 5... Bc5 gives Black play for the pawn but it is complicated, double-edged, and well-analyzed by anyone playing the White side of this: 6. Nxe5! Qe7

(6... d5 7. Bxd5 Nxd5 8. Nxd5 O-O 9. c3 (9. Ne3!? Re8 10. Nd3) 9... Re8! 10. cxd4 Bxd4 11. O-O (11. Nf3 Qxd5!) 11... Rxe5 12. d3 c6 13. Nf4 b6 14. Qc2 Rc5 15. Qe2 Ba6 16. Be3 Qd6 17. Rac1 Rxc1 18. Rxc1 Be5 1/2-1/2 Shirov,A-Kramnik,V/Cazorla 1998)

7. Nf3!

(7. Nd3?! yields bad results for White after 7... d5 8. Bxd5 (8. Nxd5 Qxe4+ 9. Ne3 Bd6 10. O-O b5 11. Bb3 Bb7 12. Ne1 Qh4 13. g3 Qh3 14. c3 h5 15. cxd4 h4 16. Qe2 Qxh2+ 0-1 Belsitzman,Z-Rubinstein,A/Warsaw 1926) 8... Nxd5 (8... Bg4 9. f3 Nxd5 10. Nxc5 Nb4 11. fxg4 Qf6 12. Nd5 Nbxc2+ 13. Qxc2 Nxc2+ 14. Kd1 Qc6 15. Kxc2 Qxc5+ 0-1 Keely,R-Miles,A/Staffordshire 1969) 9. Nxd5 Qxe4+ 10. Ne3 Bd6 11. O-O Be6 12. Ne1 O-O-O 13. c3 Nf5 14. Qc2 Qh4 15. Nf3 Qf4 16. Nxf5 Bxf5 17. d3 Qg4 18. Nd4 Qh5 19. f4 Rhe8 20. b4 c5 21. Nxf5 Qxf5 22. Qd2 Bc7 23. Rf3 cxb4 24. cxb4 g5 25. fxg5 Qe5 26. Bb2 Qxh2+ 0-1 Nimzowitsch,A-Alekhine,A/St Petersburg 1914 (44))

7... d5

(7... Nxe4? 8. Nd5! Qd6 9. Nxd4 Bxd4 10. Qe2 1-0 Schoenbach,P-Stellmacher,D/DESC email 2002 (36))

8. Bxd5

(8. Nxd5?! yields bad results for White after 8... Qxe4+ 9. Ne3 Bg4 10. Be2 Nxe2 11. Qxe2 O-O-O 12. d3 Qe6 13. O-O (13. Ng5 Qd7 14. f3 Bh5 15. Bd2 Rhe8 16. O-O-O Qa4 17. Kb1 Bxe3 18. Bxe3 Nd5 19. Ne4 f5 20. Bg5 fxe4 21. dxe4 Rd6 22. c4 Rxe4 23. Qxe4 Bg6 24. Rxd5 Rxd5 25. cxd5 Bxe4+ 0-1 Sojka,V-Kocem,E/ICCF corr 1971) 13... Nd5 14. Re1 Rhe8 15. Bd2 f5?! (15... Qg6!) 16. Qd1 Nxe3 17. Bxe3 Bxe3 18. Rxe3 Qb6 19. Rxe8 Rxe8 20. b3 Qf6 21. d4 Qe6 22. Kf1 Qe4 23. c4 Rd8 24. d5 c6 25. Ng5! Qe5 26. f3 Bh5 27. Ne6 Rd6 28. f4 Qf6 29. Qe1 Bf7 30. Qe5 Bxe6 31. Qxf6 gxf6 32. dxe6 Rxe6 33. Rd1 Re4 34. g3 Kc7 35. Kf2 1/2-1/2 Schubert,H-Aristov,V/USSR 1957)

8... Bg4 (8... Nxd5!? 9. Nxd4!) 9. d3 c6 10. Bb3 Nd7 11. Be3 Ne5 12. Nxd4!! Bxd1 13. Nf5 Qf8 14. Bxc5 Qxc5 15. d4 Qb4 16. Rxd1 and White appeared to have more than sufficient compensation for his Queen in a game with Shirov taking the Black side -- so you know White knew what he was doing: 16... Ng6 (16... g6!) 17. Nxg7+ Kf8 18. Nf5 a5 19. a3 Qb6 20. O-O Rd8 21. e5 Rg8 22. f4 Ne7 23. Nd6 Nc8 24. Nxf7 Rxd4 25. Kh1 a4 26. Nxa4 Rxd1 27. Rxd1 Qf2 28. Ng5 Rg6 29. Nxh7+ Ke7 30. Ng5 Qxf4 31. Nf3 Qe3 32. Nc3 Qf2 33. Rg1 Nb6 34. Ne4 Qe2 35. Ng3 Qf2 36. Rf1 Qc5 37. e6 Nd5 38. Nd4 Rf6 39. Ngf5+ Ke8 40. Ng7+ Kf8 41. Rxf6+ Nxf6 42. e7+ Qxe7 43. Nde6+ Kg8 44. Nf5 1-0 Motylev,A-Shirov,A/Bastia 2004.

d) 5... c6! is the newest gambit idea and looks quite promising: 6. Nxe5 d5 7. exd5 Bd6! giving Black a very speedy development after 8. Nf3 (8. O-O?! Bxe5 9. Re1 Ng4!) 8... Qe7+!

(8... Nxf3+!? is less clear but appears to yield Black enough for the pawn also after 9. Qxf3 O-O 10. h3 b5 11. Be2 b4 12. Ne4 Nxe4 13. Qxe4 cxd5 14. Qf3 Qc7 15. O-O d4!? A most remarkable way of preventing White from blocking the long diagonal with d4!!(15... Bb7 16. d4 Qxc2 17. Bd3 Qc7 surrenders the initiative to White) 16. Qxa8 Bb7 17. Qxa7 Bc5 ( Black might try 17... Bh2+!? 18. Kh1 Bxg2+ 19. Kxg2 Qxa7 20. Kxh2 Qc7+ 21. f4 Qxc2 and it is very hard for White to activate his forces) 18. Qxb7!? (18. Qa4! d3! 19. Qb5 Qg3 (19... dxe2 20. Qxe2 Qg3 21. Qg4) 20. Qxb7 dxe2 21. Qf3) 18... Qxb7 19. Bd3 Qb8 20. b3 Qf4 21. Bb2 Bd6 22. g3 Qg5 23. Kh2 h5 24. f4 Qd5 25. h4 Re8 26. a4 Bc7 27. a5 Bxa5 28. Bxd4 Qxd4 29. Rxa5 Rc8 30. Re5 Qd6 31. Rfe1 1/2-1/2 Ivanchuk,V-Svidler,P/Linares ESP 1999 (68))

9. Kf1 Nxf3 10. Qxf3 O-O 11. h3 Re8 12. g3 b5 13. Bd3 b4 14. Nd1 cxd5 15. Ne3 Bb7 16. Nf5 Qc7 17. Nxd6 Qxd6 18. Bb5 Qb6 19. Bxe8 d4 20. Qd1 Bxh1 21. Ba4 Qb7 22. d3 Bf3 23. Qe1 Qa6 24. b3 Qc8 25. g4 h5 26. Qe5 Qc3 0-1 Kristol,L-Polgar,S/Tel Aviv ISR 1999

6. gxf3!

This idea has been tried with success in the variation with Ba4.

Less challenging is 6. Qxf3 d6 7. d3 (7. O-O Be7 8. d3=) 7... Be7 8. h3 c6 9. g4 b5 10. Bb3 O-O 11. g5 Nd7 12. h4 Nc5 13. Be3 Nxb3 14. axb3 Be6 15. d4 exd4 16. Bxd4 b4 17. Ne2 c5 18. Be3 d5 19. Nf4 d4 20. Bd2 Qd7 21. Rg1 a5 22. Nh5 Qc6 23. Qf4 Kh8 24. f3 c4 25. bxc4 Qxc4 26. Qe5 Rg8 27. f4 Qxc2 28. Rc1 Qd3 29. Rg3 Qa6 30. Qxd4 Rad8 31. Qf2 Qb7 32. Qe2 Rd4 33. Re3 Rgd8 34. Rd1 Bc4 35. Qg2 b3 0-1 Wehmeier,S-Romanishin,O/Calvia ESP 2006.

6... d6

Black has a number of alternatives here, but none have yielded good results:

a) 6... Bc5 may be the best try: 7. d3 d6 8. Rg1 g6 9. f4 (9. Na4!? Bb4+ 10. c3 Ba5 11. b4 Bb6 makes it hard for White to castle but seems to yield real positional pluses) 9... Be6 10. Bxe6 fxe6 11. fxe5 dxe5 12. Bg5 Rf8 13. Qf3 Qd7! (13... Qe7 14. O-O-O) 14. Bxf6 Be7 15. Qh3 Bxf6 16. O-O-O O-O-O 17. Kb1 Kb8 18. Ne2 Rf7 White has the better minor piece and the better structure, but making that pay takes a lot of work: 19. c3 Be7 20. Rgf1 Rdf8 21. f3 a5 22. d4 Qb5 23. Nc1 Ba3 24. Nd3 exd4 25. cxd4 a4 26. Ka1 Bd6 27. e5 Be7 28. Qxe6 Rxf3 29. Rxf3 Rxf3 30. Qxe7 Rxd3 31. Rxd3 Qxd3 32. Qe8+ Ka7 33. Qxa4+ Kb8 34. a3 Qe2 35. Qe8+ Ka7 36. Qd7 Qf1+ 37. Ka2 Qc4+ 38. Kb1 Qf1+ 39. Kc2 Qe2+ 40. Kc3 Qe3+ 41. Kc4 Qe2+ 42. Kd5 Qg2+ 43. Ke6 Qxh2 44. Qxc7 Qh3+ 45. Kd6 Qf5 46. Qa5+ Kb8 47. Qd8+ Ka7 48. e6 g5 49. e7 Qf6+ 50. Kc5 1-0 Pihlajasalo,A-Molander,R/Finland 1996.

b) 6... Bb4 7. Rg1 g6 8. a3 Bd6?! (8... Bxc3 9. dxc3) 9. d4 Nh5 10. dxe5 Bxe5 11. Bxf7+! Ke7 12. Bg5+ Bf6 13. Bxf6+ Nxf6 14. Bb3 Re8 15. Qd2 c6 16. O-O-O d6 17. e5 dxe5 18. Qh6 1-0 Anilkumar,N-Juneja,M/India 1999.

c) 6... c6!? 7. d4 d5!? may be a viable gambit try, but not the way Black played it here: 8. exd5 Nxd5 (8... Bb4!?) 9. Bxd5 (9. Nxd5 cxd5 10. Bb5+ Bd7 11. Bxd7+ Qxd7 12. dxe5 Qe6) 9... cxd5 10. Qe2 Bb4?? (10... Be7 11. Qxe5 O-O) 11. Qb5+ Qd7 12. Qxb4 exd4 13. Nb5 Qe6+ 14. Kd1 Qb6 15. Bf4 a5 16. Nd6+ 1-0 Andersen,H-Groenli,F/Sarpsborg 2001.

7. d4 Be6

7... Bh3 8. Rg1 is no better, but Black can likely improve slightly here.

8. d5!

Grabbing complete control of the light squares and securing a powerful bind on the position. Ippolito seems never to have had a chance from this point on.

8... Bh3

Black's Bishop risks being left out in the cold on this square, but the alternative does not promise anything better:

8... Bd7 9. f4 exf4 10. Bxf4 g6!? 11. Qd2! Bg7 12. O-O-O O-O 13. Rde1 Re8 14. Bg5 b5 15. Bxb5 Bxb5 16. Nxb5 Rxe4 17. Rxe4 Nxe4 18. Bxd8 Nxd2 19. Bxc7 Bh6 20. Nxd6 Ne4+ 21. Kb1 Nxf2 22. Rf1 Ng4 23. Nxf7 Bg7 24. Nd8 Ne3 25. Re1 Rxd8 26. Bxd8 Nxd5 27. c4 Nb4 28. Re8+ Kf7 29. Re7+ Kf8 30. Rxa7 Nc6 31. Ra8 Kf7 32. Rc8 1-0 Najer,E-Mamedyarov,S/Khanty Mansiysk 2005.

9. f4!

Eliminating the doubled pawns while gaining an advantage in the center.

9... exf4

9... Bg2? 10. Bb5+!

10. Bxf4 Nd7 11. Rg1 Qc8 12. Qf3 Nb6 13. Bb3 h5

This seems necessary to rescue the Bishop and delay White's castling, but it is clear that Black has no useful ideas.

14. Qe3 f6 15. Qd3

The Queen probes for a way into Black's position and now eyes the g6 square.

15... a5 16. a4 Bd7 17. O-O-O Kf7?

Black's King has no better home, but now White blows open the position to exploit the weak g6 square.

18. e5! fxe5?

This allows a mating attack, but 18... Bg4 19. e6+ is equally hopeless.

19. Qg6+ Kg8 20. Ne4! Qd8

The only way to stop White's mating threat, e.g.: 20... exf4?? 21. Nf6#

21. Bxe5! Bg4

21... dxe5?? 22. d6+ lets the Bishop deliver the mate.

22. Nf6+ Qxf6 23. Bxf6 Rh6 24. Qxh6! 1-0