Marlborough heads Ayr entries Marlborough heads a host of Martell Grand National entries to stand their ground for the Scottish equivalent at Ayr on April 20th.The Stg#100,000 Gala Casinos Daily Record-sponsored marathon has 67 horses left in after the first forfeit stage, with Nicky Henderson`s 10-year-old heading the weights on 11st 12lb.Martin Todhunter`s Kingsmark is next in the handicap on 11st 9lb, followed by Paul Nicholls` Shotgun Willy (11-6), and Martin Pipe`s Cyfor Malta (11-5).Pipe`s Blowing Wind and Nicholls` Ad Hoc, who are vying for favouritism for the Aintree showpiece on Saturday, are on 10-11, along with the Ferdy Murphy-trained Paris Pike.Course specialist Grey Abbey has won six times at the track and has been allotted 10-6, although Barry Murtagh`s front runner will pick up a 6lb penalty for his victory at Wetherby on Bank Holiday Monday.