The 20 year old is currently on loan at Getafe from the La Liga champions and he has bagged three goals in 15 games from midfield for the Spanish outfit.
He also has a European U 19 Championship title under his belt with Spain and has since broken into the U 21 side.
It is thought that Madrid have high hopes for Granero for the future, so despite being at a tender age he is likely to cost Arsenal at least £7 million.