Sam Thomas will leave a decision over Iwilldoit's defence of his Coral Welsh Grand National title to the last minute.
The stamina-laden chaser has not raced since his red-letter day at Chepstow last December when he ploughed through the mud to inflict a nine-length defeat on Highland Hunter, as only five runners completed the course.
Thomas, who hails from nearby Abergavenny, has had to take his time with his progressive stayer – and admits the big race on December 27 may come too soon.
"It will be touch and go whether he makes it," he said. "He had a long time off after the race. We will decide nearer the time."
Iwilldoit was the third Welsh-trained winner of the marathon contest, run behind closed doors due to Covid restrictions for the second successive year.
Meanwhile, prospects for this Saturday's card at Haydock, featuring the Betfred Tommy Whittle Handicap Chase, look bleak.
The Merseyside turf has been frozen since last Wednesday, with overnight temperatures dipping to -5C.
“We will inspect on Thursday and are likely to call it off then," said clerk of the course Kirkland Tellwright.
Lingfield officials have scheduled a 7.30am inspection for Wednesday afternoon's card, with another chilly night forecast.
There are no concerns surrounding Kempton's twilight card, the day's other fixture after Newbury's jumps card fell to the weather.
Next year's Dubai Duty Free Irish Derby will revert to a Sunday slot for the first time since 2011 with an increased prize of E1.25 million on offer.
The Group One event, which is held at the Curragh and was won by Ralph Beckett's Westover this year, has been supported by the sponsor since 2008.
That partnership will continue into next year and has now extended to include an additional five races on the same card, scheduled for July 2.
