Folsom Blue will bid to give Mouse Morris a hat-trick of Grand National victories this spring when he lines up for the Coral Scottish Grand National Handicap Chase at Ayr tomorrow.

The County Tipperary trainer has won the first two legs of what would be an historic treble with Rogue Angel in the Irish version and Rule The World in the big one at Aintree.

Both are owned by Gigginstown House Stud as is Folsom Blue, who was a creditable fourth in the Irish National at Fairyhouse on Easter Monday.

A maximum field of 30, plus two reserves, have been declared for the marathon handicap chase north of the border.

The weights are headed by another Irish raider, the Gordon Elliott-trained Cause Of Causes. He will now carry top weight of 11st 12lb following the withdrawal of Sausalito Sunrise.

Fine Rightly, trained by Stuart Crawford, is second in the handicap on 11st 8lb after the weights were raised 4lb at the 48-hour final declaration stage.

Willie Mullins will try to extend his lead in the British trainers' championship by winning with Measureofmydreams, who, like Folsom Blue, is owned by Gigginstown.

A fifth Irish challenger is Tony Martin's Heathfield.

Seeyouatmidnight leads the Scottish charge, while several horses who missed the cut for the Crabbie's Grand National have been rerouted to Ayr.

They include the 2014 Aintree hero Pineau De Re, Becher Chase victor Highland Lodge, and Alvarado, fourth on Merseyside in 2014 and 2015.

Kerry Lee looks to Goodtoknow to continue her brilliant first season as a trainer while others in a highly-competitive field include Shotgun Paddy, Vyta Du Roc, Milansbar and Royale Knight.

Cogry, trained by Nigel Twiston-Davies, and Pauline Robson's Full Jack are the two reserves.

A total of 30 runners go to post in front of a sell-out 17,000 and Ayr officials are urging people who don’t have a ticket to watch on television as there will be no means of entry on the day.