I'd try a swap deal for Sahin +few mill from us. These kind of cheap deals with real madrid used to work for us always. Also i can see sahin playing in 4231, 4312 and 4321 and in 433 when sneijder is out and injured.
Either Poli/cambiasso, sahin, guarin; sneijder in 4312; Poli/cambiasso, sahin guarin; alvarez, sneijder in 4321 or cambiasso, sahin; alvarez, sneijder guarin/poli in 4231.
When it comes to 433, we would play different kinds of 433. Either with sneijder in the forward center midfield or sahin in the back center midfield.
One thing is sure tho - this swap would do good for both players and with sahin our midfield would bo complete with lots of options and without worrying that someone will cry for not enough playing time.
Go go branca. Make the deal.