Rainbow returns at Ascot
(Healy Racing Photos)
Nicky Henderson's charge won a thrilling renewal of the Champion Chase at Cheltenham in March before following up over two and a half miles in the Melling Chase at Aintree.
Paul Nicholls' Ghizao returned to form with a victory at Kempton earlier this month and he steps back up to Grade Two company.
The Nick Williams-trained For Non Stop tries to supplement his outstanding Old Roan Chase victory at Aintree last month.
Captain Chris represents Philip Hobbs, while Alan Jones' Quincy Des Pictons is the outsider of the group.
Navan are set to hold a 3pm inspection tomorrow ahead of Sunday's card due to the threat of heavy showers later today.