The Fillies Maiden at Navan produced a thrilling finish with Eirnin just getting up on the line to pip stablemate Diamond Brooch
Johnny Murtagh had hit the front over two from home on Diamond Brooch, taking it up from another Ballydoyle inmate Make My Heart Sing
Joseph O'Brien didn't enjoy as easy a passage on Eirnin, finding himself the meat in a sandwich at the two pole between eventual third Oh What A Kitten and 11/4 fav Haziyna (6th).
The Galileo filly, owned by the jockey's mother Anne-Marie, found her feet inside the final furlong, powering home to edge it on the line.
It was a quick double on the day for O'Brien, who put up 2lb overweight at 8-11, after the victory in the previous race of Fosters Cross
Gary Carroll currently leads the apprentice title race on 33, one ahead of Ben Curtis, with O'Brien now four behind on 29.