Tidal Bay now has a "50-50" chance of running in Saturday's Argento Chase at Cheltenham.
Paul Nicholls has declared the Lexus Chase winner at the overnight stage but his participation depends on how he responds to treatment. The problem was diagnosed as pus in his foot and his trainer says a lot can happen in 24 hours.
"Tidal Bay has marginally improved and I would now rate his chances of running in tomorrow's Argento Chase at Cheltenham at 50-50," Nicholls told Betfair.
"The problem was pus in his foot and, without getting technical, we are adopting the normal treatments and procedures in these circumstances. I have had plenty of horses with a similar problem in the past, and they have run in the same timeframe.
"It is all about how he responds to the treatment now, but we are heading in the right direction. He will be left in the race at the overnight stage, and we will make a decision in the morning. He will be given an hour on the walker this morning, and again this evening, so we will keep him ticking over. Fingers crossed."
Tidal Bay is one of 12 horses declared for the Argento. Bobs Worth, as revealed by trainer Nicky Henderson on Thursday, has been withdrawn from the final field due a bad scope earlier in the week.
Imperial Commander, the 2010 Gold Cup winner, will be having his first outing for 680 days following a rotten sequence of injuries and setbacks. Nigel Twiston-Davies' 12-year-old will be joined in the line-up by stablemate Little Josh, who won the Grand Sefton at Aintree in December.
Grands Crus, third in the King George VI Chase at Kempton last time, is also engaged for the David Pipe team. Hunt Ball is being campaigned for the Betfred Cheltenham Gold Cup and has been given the green light by his colourful connections.
Weird Al is an interesting contender on his first start since finishing fourth in the Betfair Chase at Haydock, while Cape Tribulation takes his chance for Malcolm Jefferson. Last year's winner Midnight Chase will attempt to atone for being pulled up in the Lexus Chase at Leopardstown over Christmas.
The rejuvenated Wayward Prince has also been declared by owner-trained Hilary Parrott. Calgary Bay, Hey Big Spender and Quartz De Thaix complete the field.
2 March 2015Watering possible at Cheltenham
Wincanton Thursday abandoned
Aintree beckons for Milan
Dundalk unlikely for Byron
Cops on patrol for Pertemps
Sizing team to make late call
Stars on show at Cheltenham
Codd angling for Festival glory
Duke set Carlisle agenda
Prospects bleak at Wincanton
Moon camp wary of Irish threat
Hobbs unveils Cheltenham hopes
Magic McCoy on target with Fredo
Azorian back in winning groove
Berlais lands Auteuil prize
Fred Winter favoured for Berbas
High hopes for Meade Festival team
Cooper seeks Cheltenham riches
Lemaire in hot water in Japan
Reckless camp consider Arkle bid
1 March 2015Cecil runner second at Huntingdon
High hopes for Meade Festival team
Super set for National Duty
Longsdon retains Joe faith
Nolan hoping Noble makes cut
Camping in line for Cup bid
Bin Suroor tribute for Cavalryman
Vautour excites Mullins in workout
Elliott posse work at Leopardstown
Geraghty confirmed for Master
Wayward back on right track
Investment gains Greatwood gold
Bal win delights connections
Glinger burns off Kelso rivals
Pipe proves he's a Soll man
Geraghty shines on Leave It
28 February 2015Festival plans fluid for Cyclone
Walter back for another victory
Irish pair do battle in France
Geraghty: Sprinter will be fitter
Wylie lines up Cheltenham team
Twiston-Davies Blak in business
Divine Bishop on Festival trail
Irish duo set Doncaster poser
Night riding high for Grimthorpe
Glingerburn facing another battle
Pipe targets Aintree with veterans
Carlito primed for Kelso return
McCoy not planning Festival goodbye
Bridge camp praying for rain
Cook suspended from riding
27 February 2015Golantilla in Ballsbridge bid
Safety strikes in Zabeel Mile
Fehily confirms Zarkandar mount
Lieutenant bosses Purcell rivals
Dettori delights on Dubday
Many Clouds goes back to school
Maguire loses appeal
New One at ease for Faugheen clash
Foxrock still in Gold Cup picture
Apache ready to take flight in JLT