Thiller at Down Royal The Ulster Harp Derby, Northern Ireland`s richest flat race, ended in a dead-heat for the first time in its 39-year-old history when the 13-8 favourite Masilia and the 7-1 chance Citizen Edward could not be separated at Down Royal today.Jockey Johnny Murtagh, the hero of Royal Ascot, appeared to have the race won on Masilia who took the lead in the final furlong.But Citizen Edward came with a tremendous run from the back of the field to go a neck in front as the post loomed. Murtagh fought back on Masilia and both horses crossed the line locked together.After 12 minutes the judge could not separate the pair in the photograph and a dead-heat was announced for the first time since the race began in 1962.Murtagh said: 'I saw Seamus Heffernan coming up on my outside on Citizen Edward and he went a neck in front. I got to work on Masilia and I thought I had got up.'Citizen Edward is trained by Jim Bolger, who wasn`t at the meeting, but John Oxx, who trains Masilia said: 'I`m happy with that result. She did everything right to win but ran a bit green when she struck the front.' David Cosgrove`s British raider Tough Leader finished down the field.