Al Ferof and Finian's Rainbow feature among eight confirmations for Saturday's 25th Anniversary of the Victor Chandler Chase at Ascot.
This prestigious £105,000 contest, one of Ascot's premier Jumps races, is due off at 3.10pm (GMT) and run over two miles and one furlong (3400 metres).
Finian's Rainbow, trained by Nicky Henderson, is the highest British-trained horse in the betting for the Queen Mother Champion Chase and will bid to enhance his Cheltenham Festival claims on Saturday.
Champion trainer Paul Nicholls has a major hope in exciting novice Al Ferof, while Tom Cooper's Forpadydeplasterer could make the journey from Ireland.
If he travels he will attempt to become the third Irish-trained horse to win the race, but the first since it was promoted to Grade 1 level in 2007.
The 2009 Arkle winner has not won since that Cheltenham victory, but he has run very well in defeat on a number of occasions since and trainer Tom Cooper was delighted with his third behind Big Zeb at Leopardstown over Christmas.
Henrietta Knight's Somerbsy and the Philip Hobbs-trained Wishfull Thinking are other major contenders, along with Gauvain from the in-form Nick Williams stable.
Wishfull Thinking has disappointed thus far this term and there are doubts about his breathing but if he returns to anywhere near his best he could still be a live contender.
I'm So Lucky and Oiseau De Nuit complete the entries.
Up at Haydock Park, David Bridgwater is targeting The Giant Bolster at the £50,000 The Peter Marsh Chase over three miles (4800 metres), which is due off at 3.30 pm.
The seven-year-old has had his jumping problems over the past couple of seasons, but Bridgwater hopes those are behind him following two consecutive clear rounds at Newbury.
The Giant Bolster chased home Time For Rupert following a creditable seventh in the Hennessy Gold Cup.
Bridgwater expects him to be back on the track this weekend, with Haydock currently favoured over Ascot, where he is also engaged.
He said: “The Peter Marsh has been the plan since he ran at Newbury, so hopefully he'll run in that, but he wouldn't want the ground too heavy - hopefully a bit of frost might dry it out a bit.
"He's had two nice schooling sessions, and now we have to find out how much of a man he is. We have to put the gun to his head and find out what happens."
The Giant Bolster is one of 18 Peter Marsh Chase possibles, with Malcolm Jefferson having entered Rowland Meyrick winner According To Pete, along with stablemate King Fontaine.
Other interesting contenders include Nicky Henderson's Shakalakaboomboom, recent course winners Tamarinbleu and Bold Ransom and 2009 John Smith's Grand National hero Mon Mome.
