Miss Xian narrowly outpointed Bothair Clei in a pulsating climax to the Woodlands Park 100 Club Leinster National at Naas.
Three miles faced the eight runners in the feature event of the afternoon and Allied Victory cut out much of the running before Mark Enright bustled Miss Xian to the front rounding the turn for home.
Sonny B travelled ominously well into the straight and joined Miss Xian on the run to the final fence, with Bothair Clei also in contention to make it a three-way battle on the run-in.
Bothair Clei looked set to triumph after hitting the front, but 9-2 chance Miss Xian roared back and the two passed the post virtually as one.
After a brief wait, the judge called Fran Flood's mare the winner by a nose.
Enright said: "I didn't know (if I'd won). The angle can be very deceiving here.
"She's tough and I wanted to make plenty of use of her. I wanted to ensure we went a good pace all the way and I wanted to get on terms jumping the last down the back. I really needed to kick on as she just gallops."
Flood said: "That's worth a lot. It's a great race, the Leinster National.
"We took a big chance being 6lb out of the handicap, but that's her third win around Naas and she's tough and she stays.
"It's a black type race and it's worth a lot to a mare, so it's worth taking a chance.
"I suppose the three-mile-five (furlong) in Punchestown would be a race that springs to mind. We'll see what the handicapper does to her."
Fine Rightly battled on bravely to land the Grade Three Naas Directors Plate Novice Chase.
Davy Russell was happy to cut out the early running on the 6-1 chance, and the jockey was unperturbed when Azorian edged ahead before the home straight.
Still travelling best at the second last, he ran on well, but was hard at work to repel the late challenge of Rule The World by a length. Hot favourite Noble Emperor crashed out early on.
Russell made it two doubles in as many days when driving Fletcher (20-1) into the lead after the last to land the Naas Supporters Handicap Hurdle for trainer Eddie Harty.
Phil's Magic took the step up to Listed company in his stride when leading home a Sandra Hughes one-two in the irish Racing Writers Kingsfurze Novice Hurdle.
Settled off the pace by Johnny Burke, the 6-4 favourite made steady headway before joining stablemate Prince Of Scars at the last.
He found more up the run-in to score by half a length.
Rossvoss ran out a wide-margin winner of the Hospitality At Naas Racecourse Beginners Chase.
Favourite Tennis Cap and Kick On Boss shared pacesetting duties, but Sean McDermott tracked the pair on Ted Walsh's 14-1 chance before striking for home in the straight, pulling clear to beat Kick On Boss by 15 lengths.
Gordon Elliott's Captain Von Trappe (7-2) found enough for Davy Condon up the run-in to repel Golden Boot and land the Network Ireland Kildare Branch Supporting International Women's Day Maiden Hurdle.
Katie Walsh booted home Tara Flow (10-1) to upset odds-on favourite Last Encounter in the Tipper Road Flat Race.
