In this Anderssen variation, I played through theory until move 8 where Be7! puts white up a full point. Instead, the reoccurring Sicilian theme of a6! was needed to prevent whites knights from taking advantage of the open light squares and pummeling the position. Although 10...0-0 was the correct continuation, white has too many available continuations including the line played by my opponent and even simpler 11.Nxe7 followed by 12.Qxd6.
The Anderssen variation avoids both the English and Yugoslav Attack because of its d5 option. However the a6 theme is so important that some players opt for the Kan variation sidesteping both 4.Nf6 and Nc6 for a6! to block to white knights from quick advancements, but also preventing Bb5 pinning ideas. It's also has many creative possibilities.
Finally, the most popular and respected Najdorf variation is known for it's early 5.a6 move to provide the same defenses as the Kan on the queen side.