The Daily Mail says Arsenal are considering a dramatic move for Casillas as they step up their pursuit of a replacement for error-prone Wojciech Szczesny.
The Spain captain is known to be unsettled at the Bernabeu after losing his automatic place in the first team under Jose Mourinho and the Gunners are keeping a close eye on his situation.
Although Arsene Wenger is keen on Casilllas, the stumbling block could be his price. Casillas is 32 and ever-prudent Arsenal do not want to pay big money for a move knowing full well they cannot sell him on.
They would consider a fee of around £8million but fear Madrid would not listen to offers below the £15m mark.
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