4.e3 Bc6 5.Qd1 Rfd8 6.Qf1 b5! 7.Ba5 Re8 8.Rad1 Qxe5 9.Bxd5 Bxd5 10.Bc3 Qe6 11.Rxd5 a6
A "mysterious" rook move, realizing that Black's only viable plan is ...b6-b5.
Some more prophylaxis in order to cover the sensitive second rank. Meanwhile, Black is just playing with one rook, since the one on f8 is tied to the defence of f5.
It doesn't seem right to abandon the seventh, but there weren't many moves to choose from.
In view of the coming Rc2-g2, Black protects the g7-pawn in advance and prepares a further reinforcement of the kingside by ...Bf8 and ...Ne7-f5.