GM Petrov's Mastering the Sicilian Sveshnikov - Video 10

In this video, we will see the most critical line when after Bf6 white goes c3. He wants to play Nc2, then Ne3, and combine both a4 or even h4 in some situations.
Black has 4 different moves. Some of them could transpose.
Either he immediately plays Ne7 before the other knight comes to e3. In this case, white has to take the bishop and double the pawns, but then black could prepare a fast d5 and activate his pieces.
The other lines are a castle, Bg5, or Rb8. The early move with the rook intends to meet a4 with ba4. The bishop's move is to prepare Ne7 without allowing Nf6.
In most of the lines, black has a good game.