Since the late 1980s, Black has increasingly chosen to play 6…Qb6 against White’s attempt to play the Velimirovic Attack. This is more due to personal preferences to play other types of positions instead of facing the Velimirovic. Black has done quite well with this line regardless of how White continues now.
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Our starting position typically arises after 1.e4 c5 2.Nf3 Nc6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 d6 6.Bc4 Qb6 (or 2…d6 and 5…Nc6). We will now learn a promising system for White that will offer chances for a positional edge as well as tactical complications.

7.Be3?! is a desirable move in these types of positions, but should not be played when Black’s queen can safely take the b2-pawn. After 7…Qxb2, Black is fine due to the resource …Qb4, e.g., 8.Ncb5?? Qb4+ and 8.Ndb5 Qb4 and the queen can next retreat to a5.

7.Nxc6 appears to help Black improve his pawn structure, but this move gives White chances for the initiative due to his edge in development. The most popular move here is 7.Nb3, but Black has done well in practice with 7…e6. Then both 8.Bf4 Ne5 9.Bb5+ Bd7 10.Bxd7+ Nfxd7 11.Qe2 and 8.Be3 Qc7 are fine for Black. 
A sharp alternative is 7.Ndb5 a6 8.Be3 Qa5 9.Nd4. Black has then tried all 9…e6 10.0-0 Be7, 9…Ng4 10.Nxc6 bxc6 11.Bd2 and 9…Ne5. The more patient approach 7.Nde2 e6 8.0-0 Be7 9.Bb3 0-0 10.Kh1 a6 is also playable, although it doesn’t try to pressure Black in the opening.

7…bxc6 is Black’s natural recapture. Black’s pawn on c6 now controls the d5-square, while this capture gives Black a half-open b-file instead of a half-open c-file. Note that taking White’s knight with the queen would lose the lady to a pin following 7…Qxc6?? 8.Bb5.
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In the Open Sicilian White’s main job is to pressure Black to weaken his solid position.

Castling kingside with 8.0-0 improves White’s piece coordination and is his best option. White delays the question how to deal with developing the c1-bishop without losing the b2-pawn until after he sees how Black continues his development.

8…g6 is one of Black’s common moves in this position. Black is trying to fianchetto the f8-bishop to g7 next and castle kingside. His position would then be quite safe. Black’s most solid alternative is 8…e6, when 9.Qe2 Nd7 10.b3 Be7 11.Bb2 0-0 12.Na4 Qc7 is unclear. Note that 8…e5 is more risky since White can launch a quick attack with 9.Bg5 Qxb2 10.Qd3 Qb6 11.Bxf6 gxf6 12.Nd5!
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White needs to act quickly to disturb Black’s solid position before Black completes development.

9.Be3!? attacks Black’s queen and is the most aggressive continuation. A slower approach is 9.Bd3. This was played in Velimirovic-Csom (1977) and has the interesting plan of meeting 9…Bg7 with 10.Na4 Qc7 11.f4 0-0 12.c4. White would then have a slight space advantage.

9…Qxb2 takes the offered b-pawn. This is quite dangerous though as White now gets tactical compensation due to his better piece development. If Black retreats the lady with 9…Qc7, White can continue with 10.h3 Bg7 11.Qd2 0-0 12.Bh6 or 10.f4 Bg7 11.h3. White would obtain a promising attacking position following 9…Qa5 10.f4 Bg7 11.h3 0-0 12.Bb3.
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Conducting an attack requires just as much precision as defending against one.

Be more careful! 10.Ne2? retreats the attacked knight to a passive square. Did you really hope for Black to fall for the trap 10…Nxe4 11.Bd4? Black would stand better after 10…Bg7.

10.Bd4!? protects the c3-knight and now threatens discovered attacks against Black’s queen by the c3-knight. This is the only move that allows White to keep the initiative.

10…Qb4 gets the queen off the dangerous a1- h8 diagonal and attacks White’s bishop on c4. Black has to avoid the passive 10…Qb7, as then 11.Bxf6 exf6 12.Nd5! gives White a strong attack. Perhaps the odd looking 10…Qa3 is playable. 
Note that 10…e5?! instead is quite risky. White then has many options, but the straight forward 11.Rb1 Qa3 12.Rb3 Qa5 13.Be3 appears the best. Then White earned an edge in Bosch-S.Polgar (1997) following 13…Be7 14.Bg5 Qc5 15.Bxf6 Bxf6 16.Qf3. Black faces a difficult task getting his pieces to good posts in this line.
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Will Black’s queen be the hunter or the hunted?

Your move allows Black to win your c4-bishop with 11…Qxc4 next. Pay more attention to your opponent’s last move.

11.Be2? is a passive retreat by the attacked bishop and gives Black time to start a counter attack with 11…e5. If you then moved the d4-bishop, Black could win the c3-knight for free. Note that inserting the moves 12.Rb1 Qa5 would not help White’s position.

11.Bxf6 destroys Black’s kingside pawn structure and doesn’t give Black time to take the c4-bishop now since Black’s rook on h8 is attacked.

11…exf6 is the only reasonable move. Black now has the bishop pair, but is still behind in development and has several vulnerable pawns.
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Note that only Black’s queen has left its original square. This type of single handed adventure by a queen in the opening is often too dangerous.

12.Qd3?! protects all loose minor pieces with the queen. But this is too slow and gives Black time to catch up in development with 12…Bg7.

12.Qd4! does not only protect the c4-bishop, but also threatens to win Black’s queen with the discovered check Bxf7+ on the following move. Note that the f6-pawn is now also attacked.

12…Ke7 is a hard move to play, but there are no good alternatives as both 13.Bxf7 with check and 13.Qxf6 were threatened. The only reasonable alternative 12…Be6 runs into 13.Nd5! Taking this knight with 13…cxd5 then gives White a powerful attacking along the e-file following 14.exd5. If Black chose 13…Qc5 instead, White would remain in control with 14.Nc7+ Kd7 15.Bxe6+. It is a little surprising that quite a few grandmasters have played into this position with Black.
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The c4-bishop separating the two ladies is a tactical motif worth remembering.

13.Rab1 gains control of the open b-file and pushes Black’s lady further away. Note that 13.Rfb1?! would not be as affective if play continued in the same manner. Black could have better chances to stay in the game by playing a timely …f6-f5 and …Bg7.

13…Qc5 appears to stop White’s attack, but things are not always as easy as they seem. If Black opted for 13…Qa5 instead, White could continue in the same manner and would have even better attacking chances with the queens on the board.
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The key moment has arisen.

14.Qxc5? is not the correct move order. After 14…dxc5 15.Nd5+ Kd8 16.Nxf6 Bg7, Black is well and alive.

Moving a rook to d1 protects your queen, but is too defensive minded. We would like to keep the initiative with active moves.

14.Ne2? protects your queen, but is too slow. We would like to force Black to react to our moves and not give him time to catch up in development with moves such as 14…Bh6.

14.Nd5+! is the hardest move to find in this line. If White traded queens with 14.Qxc5? instead, Black would have additional defensive options.

14…cxd5 is forced as 14…Kd7 15.Qxf6 gives White a decisive edge after both 15…Qxc4? 16.Qxf7+ and 15…cxd5 16.Bxd5 and Black will lose both of his rooks!
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The conclusion will be surprisingly simple.

15.Qxc5 trades queens. This marks the end of White’s attacking goals and transitions into an endgame. Note that 15.Qxd5? instead gives Black the chance to finish development and stay ahead with two bishops for a rook following 15…Be6 16.Qb7+ Bd7 17.Qxa8 Qxc4.

15…dxc5 takes White’s queen.
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Most attacks don’t lead to mate. One must be satisfied to reach other types of advantages that will allow one to get the full point a bit later.

16.Bxd5 traps the rook on a8 and gives White a very favorable endgame. After 16…Ba6 17.Bxa8 Bxf1 18.Kxf1 f5, material would be even, but White will soon get his rook to the seventh rank. Black will then find it difficult to keep the weak pawns on a7 and f7, while he is trying to get his bishop and rook out of the cave. The game Bosch-Kharlov (1993) continued with 19.Rb7+Kf6 20.Rxa7, while White also got a winning position with 19.exf5 Bg7 20.Rb7+ Kf6 21.Rxa7 in Morovic-Ricardi (1997). 
You may wonder what would have happened if White had moved the other rook from f1 to b1 on move 13. After all Black would not have had the resource …Ba6 at move 16. We can imagine the position after 16.Bxd5 with White rooks on a1 and b1 instead of b1 and f1. Black could then continue with 16…Bg7!? and meet 17.Bxa8 with …f5. Then 18.e5 Bxe5 19.Re1 Kf6 20.Rad1 allows White to stay ahead an exchange for a pawn. But the realization of this small advantage would require good technique and quite some time, whereas our chosen line gives White a clear advantage and easy path to follow. 
You have just learned a nice tactical line against the 8…g6 line of the Anti Velimirovic. It was very instructive to see how Black’s lone queen moved all over the board at the expense of neglecting development. Black was able to stop the attack against his uncastled king, but only at the cost of reaching a passive endgame position. If Black wants to play this line, he will probably need to look for improvements at move 9. Play against the 8…e5 system is usually also quite tactical, while 8…e6 will lead to more positional patterns. Both systems give White fine chances for an edge. If you want to test good alternatives for White, both 7.Nb3 and 7.Ndb5 are worth exploring.