Heavy rain this week has placed Thursday's meetings at Haydock, Nottingham, Uttoxeter and Yarmouth in doubt with all four facing inspections.
Both Haydock and Yarmouth raced on Wednesday without any problems, although conditions were attritional.
Yarmouth will hold a precautionary inspection at 7am, with further overnight rain forecast on already heavy ground.
Haydock inspect at the same time after a huge amount of rain in the past week and more forecast overnight.
Nottingham will inspect at 8am with the potential for a further 15-20 millimetres before racing, with areas of standing water in the public enclosures causing concern.
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Uttoxeter hold a precautionary inspection at 8am following 40 millimetres of rain in the past 24 hours.
Despite 52 millimetres of rain at Newbury on Monday and Tuesday, there are no reported problems with the going soft.