Hot favourite Djakadam is among a field of 19 declared for Saturday's Hennessy Gold Cup at Newbury.
Willie Mullins' youngster will be attempting to create history as a five-year-old has yet to win the prestigious handicap.
It is also a race in which Irish-trained horses traditionally do not fare well, although Mullins did win the 2002 renewal with Be My Royal only for the gelding to be disqualified subsequently.
Djakadam is the only Irish representative in the historic race.
Heading the weights are Venetia Williams' Houblon Des Obeaux and last year's winner Triolo D'Alene for Nicky Henderson.
Others near the top of the handicap include 2013 runner-up Rocky Creek, David Pipe's Ballynagour and Alan King's RSA runner-up Smad Place.
Philip Hobbs' Fingal Bay has his first run over fences for nearly two years, although he has won over hurdles at the Cheltenham Festival in the meantime.
Oliver Sherwood's Many Clouds will have plenty of supporters after a fine comeback win at Carlisle, while Neil Mulholland's The Druid's Nephew has shown improved form for his new handler.
Dan Skelton's What A Warrior has won both his starts since moving from Nigel Twiston-Davies, while Anncacotty runs for Martin Keighley and was a Grade One winner as a novice last season.
Tony McCoy has returned from injury in time to partner Jonjo O'Neill's Merry King, fifth in last year's race.
The Hennessy is one of very few major races the perennial champion has yet to win.
Wychwoods Brook, Monbeg Dude, Unioniste, Vino Griego, Via Sundown, Midnight Prayer and Le Reve are the other runners.