It looks like Galatasaray will not be signing Diogo Costa from Porto after all. The goalkeeper had been heavily linked throughout the window, but the deal is now dead in the water. Reasons for the collapse remain unclear, though it marks a blow to Galatasaray's plans to bolster their squad. The transfer has collapsed, but Diogo Costa could still emerge as a target for other linked sides such as Aston Villa. Galatasaray's back line has been a real strength this season, conceding just 0.29 goals per game (2 in 7). Diogo Costa would be expected to slot into that unit and hold his own in an already solid setup. Alongside this, Porto are said to be exploring Kenneth Taylor, Piero Hincapie and Pablo Rosario with Galatasaray likewise connected to Guillaume Restes, Senne Lammens and Wilfried Stephane Singo. Follow us on Twitter @PlayerSwitchCom and get the latest Galatasaray transfer news and rumours direct to your feed.