The Australia vice-captain was due to represent Oval Invincibles this summer and could be the first of a raft of players to decide against participating
The Hundred - women fixtures 2021
The Hundred squads 2021: Full men's and women's player lists
Rachael Haynes, the five-time World Cup winner with Australia, has pulled out of The Hundred.
The 34-year-old had agreed to represent Oval Invincibles in the inaugural edition of the eight-team competition.
Haynes was due to be among 12 Aussies to feature this summer but the ECB are fearful that number could be cut significantly.
Evening Standard understands several other players are considering pulling out because of complications around travel amid the Covid-19 pandemic.
Australia's players, for example, would have to quarantine for two weeks upon returning home, if they chose to compete.
The likes of Ellyse Perry, Meg Lanning and Alyssa Healy and Beth Mooney are all currently scheduled to feature. The tournament gets underway on July 21.
"We’re disappointed to lose a player of Rachael’s stature and ability, but the realities of COVID mean there remain practicalities that are difficult for some overseas players to overcome," an ECB spokesperson told Standard Sport.
"A replacement overseas player will be signed by Oval Invincibles, and we look forward to showcasing the women’s game with world-class players performing on a big platform through The Hundred this summer."
It remains to be seen what knock-on effect this has on the men's competition.
David Warner, Aaron Finch, Glenn Maxwell and Adam Zampa are among nine players with contracts for the 100-ball tournament. Their participation is already complicated by the white-ball tour of the West Indies which could be followed by matches in Bangladesh.
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