Monreal passed a medical at the club’s London Colney training base on Thursday night after jetting into the capital and has agreed to sign a four-and-a-half year contract.
The Londoners centred their deadline-day sights firmly on Spain as Arsene Wenger made a late bid to shore up his leaky defense.
Monreal, who has won nine caps for Spain, is Arsenal’s only signing of the January window despite Wenger having around 58 million euros available to spend. Because he has played for Malaga in the Champions League, Monreal will not be eligible to play for Arsenal when it takes on Bayern Munich in the round of 16 in three weeks.
Monreal emerged as Wenger’s specialist left back target to provide competition for Kieran Gibbs, who suffered a thigh injury against Liverpool on Wednesday night.
The Arsenal boss has lost faith in Gibbs’ deputy Andre Santos, who could be offloaded to Fenerbahce or Galatasaray before the Turkey window closes on Friday.