Doncaster clerk of the course Roderick Duncan is braced for rain on the eve of the William Hill St Leger meeting and warned that, if forecasts are correct, the word heavy could reappear in the going description.
Duncan altered the going description from soft, heavy in places to soft all over on Tuesday as the course benefited from drying conditions, but that improvement could be short-lived if the forecast rain materialises on Tuesday night and into the early hours of Wednesday.
"It's dried a bit and it's on the better side of soft now, but all the forecasts seem to be for rain tonight, with 6mm-plus possible," said Duncan on Tuesday afternoon.
"We've had lovely, drying conditions today and that's made a difference, but if the rain comes we'll be back to where we were on Monday.
"The rain is forecast to have gone through by midnight and it's then forecast to be dry, blowy and reasonably bright for most of Wednesday."
Among those hoping for a drier night than forecast will be connections of St Leger contender Stradivarius, who was eased to 6-1 (from 5) by a number of firms on Tuesday.
Sponsor William Hill went a biggest-priced 13-2 about the John Gosden-trained colt, and the firm's Rupert Adams said: "He's not completely friendless but will definitely need the ground to dry out, so we're very happy to lay him at this point. If anything we'd expect Coronet to be the better backed of John Gosden's pair."
For Sky Bet, Michael Shinners said: "The two that have been popular are Venice Beach, who we shortened from 12-1 into 10-1, and Defoe. We wouldn’t be surprised if we had co-favourites in the coming days."
Bet365 and Paddy Power were already of that opinion, quoting Capri, Crystal Ocean and Defoe as their 4-1 market leaders.
Brian Meehan has been handed a late jockey booking headache after Jamie Spencer opted to ride Deauville in the Woodbine Mile in Canada instead of Raheen House in the Classic.
The trainer admitted he had been taken by surprise by Spencer's decision and was on Tuesday evening working to find a replacement for the jockey who has ridden the horse on each of his last three starts.
"There was some mention of it earlier in the week and I contacted Jamie, and he told me he would be fine for Saturday, so this has come out of the blue a bit really," said Meehan.
On the condition of 12-1 shot Raheen House as the race approaches, Meehan added: "He's in top order, I couldn't be happier with him. He worked really well this morning and rain is not going to be a problem for us."