Pablo Armero: Napoli full-back loaned to West Ham

The Hammers lost defender Joey O'Brien to a dislocated shoulder in the 0-0 draw at Chelsea, and the problem looks likely to rule him out for the rest of the current campaign.

West Ham manager Sam Allardyce wasted little time in agreeing a deal for Armero.

A club statement said: "West Ham United are delighted to announce the signing of Colombia international Pablo Armero on loan until the end of the 2013/14 season."