The Running Foxes, One-Day Cup winners last term, begin their Division Two season at Yorkshire at Headingley on April 5 but will do so without one of their winter additions
Will Pucovski has pulled out of his overseas stint at Leicestershire after suffering another concussion.
The 26-year-old, whose career has been laden with blows to the head, retired hurt during Victoria's Sheffield Shield match against Tasmania after being struck by Riley Meredith.
It was his latest comeback having been hit while playing for the second XI in early February – days after his move to Grace Road for the first five County Championship matches had been confirmed.
The deal has now been torched with Leicestershire due to confirm a replacement later on Thursday (March 14).
Their campaign begins at Yorkshire at Headingley on April 5, a repeat of last season's opening fixture.
Pucovski was struck by a Riley Meredith bouncer in a Sheffield Shield game (Steve Bell/Getty Images)
Pucovski had been enlisted to stand in for allrounder Wiaan Mulder, who is due to arrive late for his third season due to the deep-running South African domestic season.
"It's a huge shame to lose Will at this stage, but his health must come first," said director of cricket Claude Henderson.
"Given the proximity to the start of the English season, it has been agreed by all parties to allow him the necessary time to recover, and we want to wish Will all the best as he continues to recuperate in Australia.
"Our recruitment team have been aware of the evolving situation, and we have plans in place to ensure our team is as strong as possible heading into the season. As such, we will be able to announce a new overseas addition shortly."
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