Last year's winner Sizing Europe heads a quality field of eight declared for Wednesday's sportingbet.com Queen Mother Champion Chase at Cheltenham.
Henry de Bromhead's 10-year-old is likely to be a warm order to repeat his win of 12 months ago when he defeated the previous year's winner Big Zeb.
The latter will try to regain his title, but was beaten 15 lengths by Sizing Europe in the Tied Cottage Chase at Punchestown last month.
However, Colm Murphy is expecting a better performance from Big Zeb this time.
There is a third Irish challenger in the shape of the Noel Meade-trained Realt Dubh, who was third in last year's Arkle.
Heading the home brigade is the Nicky Henderson-trained Finian's Rainbow, runner-up in last year's Arkle.
Completing the line-up are Gauvain, I'm So Lucky, Kauto Stone and Wishfull Thinking.
The two withdrawals at the 48-hour final declaration stage were Somersby and Blazing Tempo, who both hold entries in Thursday's Ryanair Chase.
