6. e6 is the main line; at the time I assumed my opponent was headed towards a line following the variation: Sicilian Richter-Rauzer, Rauzer attack, 7...a6 defence, 8...Bd7. Instead he went down a different path.
7. Qd1d2 h6
I thought this was a very interesting move. The intention I believe is to force an exchange where black can open up a semi-open file along the g-column and put pressure on the kingside. In exchange black sacrifices pawn structure.
8. Bg5xf6 gxf6 9. O-O-O
At this point we are both following a database (I will assume the same for my opponent) and some book theory (on my own behalf). Bologan V. (2688 ELO) Vs. Malakhov V. (2715) 1 - 0 2009 Sibenik is a good example of a game that follows this line.
At this point I had to decide between this move or Rhg1. I do not like the idea of keeping my rook pinned to protecting the the pawn, and with my pressure on the d file, I wanted to push f4 and take a strangle hold on the center. With g3 I was worried about Bg4 and potentially moves to either f3 or e2 being a potential nuissance.
This move took the game out of the database stage. Black attempts to control the c file and put pressure on castled King.
Continued with plan...
?? I do not like this move. I have already accomplished my goal of putting more pressure on the center. Black needs to continue with development. Much better was e6 and then getting the Bishop out and giving the king some room to breathe.
!! This was what I call the critical juncture for the match. I had several options including Rd3 mobilizing the rook, looking to possibly double the rooks later on and protecting the knight on c3. Bb5 at first seemed riskier but intuitively seems more effective in driving for an advantage. I assumed black would follow with Kd8 and after 15 Rd3 black would exchange the rook and a pawn for the knight and bishop. Personally I feel the opponent which exchanges the rook-pawn almost always finds a material advantage so I can understand why black chose the exchange. But it is also a surprise because it does end up costing him the game. With black's king traped in the center of the board this exchange allows white to increase pressure on the king with few options for black in terms of defense.