Of course, SWP is a long way from going at the moment but City boss Stuart Pearce is believed to be lining up a replacement should Chelsea or Arsenal give City an offer they can't refuse.
The 22-year-old also plays on the right and, according to the Mirror, Pearce is hoping to be able to prise him away from Feyenoord for £4m.
Castelen is a current Holland international and impressed during the goalless friendly with England at Villa Park in February, when Shaun made his first England start.