Fleming's decision follows fellow former New Zealand skipper Daniel Vettori opting not to renew his contract with Brisbane Heat.
Melbourne Renegades secured a stunning BBL08 Final victory, defeating the city rivals Melbourne Stars by 13 runs to lift their maiden Big Bash trophy
Melbourne Renegades set up a Melbourne derby with a three-wicket win against Sydney Sixers, booking their first-ever BBL Final
Stars made it to their first Big Bash final since the fifth season with a six-wicket victory over table-toppers Hobart Hurricanes in first semi-final
Unfortunately for the Sixers, their hopes of securing a spot in semi-final were quashed as they were bowled out for meagre 74.
The Thunder needed to win the rain-affected contest in just 11.3 overs to claw themselves back into the top four.
Jonathan wells (69 off 42) and Harry Nielsen (44 off 29) had other plans as the pair added 88 from 55 balls.
Vettori has been coach since 2015 and will end his tenure when the season finishes.
Heat chased down 157 in 10 overs with 10 wickets to spare, hitting 13 sixes and breaking a number of records
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