Middlesex have confirmed that plans have been in place for some time to replace Adam Voges.
Following his inclusion in the Australia squad for June's tour of the West Indies and then The Ashes, Voges will only be available for the opening four matches of the County Championship season.
However, Middlesex have revealed that they had prepared for this scenario, with a new overseas signing expected to arrive shortly.
"All of us at Middlesex are naturally delighted for Adam on his deserved inclusion in the squad, however this does leave us with the difficult problem of needing to find a replacement overseas player for the 2015 season with some immediacy," read a statement on the club's official website.
"Given the record-breaking form that Adam has been in this winter in the Sheffield Shield for Western Australia, his call-up to the Australian squad became increasingly likely with every run scored, and towards the end of the Shield campaign became almost an inevitability, so we have for some time been working on a contingency plan in the event that this became a reality.
"Conversations have been had, a shortlist of suitable players has been drawn up, and in light of this morning's announcement by Cricket Australia we can now begin to formalise these plans to secure a replacement."
Middlesex begin their campaign against Nottinghamshire on Sunday, April 12.