England fast bowler Steven Finn will take over the Middlesex captaincy throughout the club's Royal London One-Day Cup campaign if, as expected, Dawid Malan is on Test duty.
Finn, currently sidelined through injury, will have the club's long-standing wicketkeeper batsman John Simpson as his vice-captain throughout the 50-over competition.
The 29-year-old, who has 69 one-day international caps, said: "I am delighted to have been asked to captain the side in David's absence.
"Having played at Middlesex since the age of 15 I am extremely proud to have been given this opportunity and we can hopefully move the side forward in white-ball cricket and achieve success in this year's competition."
Middlesex's 50-over competition under their prospective new leadership duo begins on 17th May when they take on Lancashire in a day-night fixture at Old Trafford.
"Steven is at the stage in his career where he is very keen to take on greater responsibility and, with the expected absence of Dawid Malan with England, he is highly likely to get the opportunity to guide the club through most of our Royal London group games," said Middlesex managing director of cricket Angus Fraser.
"John is in a similar position to Steven and the pair will have the brain and experience of Eoin Morgan to help guide them.
"These opportunities are great for the development of both players and I look forward to watching them at work."
Middlesex are 1212/1 to win the Royal London One-Day Cup, with Nottinghamshire 1212/1 and Yorkshire 1212/1.
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