Mi Lighthouse was left clear to take the honours in the mares' maiden hurdle at Limerick.

Her stablemate and 8/11 favourite, La Prima Donna led and was still on good terms with herself as Mi Lighthouse improved to challenge her at the penultimate flight.

The whole complexion of the race changed there as La Prima Donna jumped it well but appeared to stumble a couple of strides later and gave Jack Foley no chance as she fell.

Mi Lighthouse was left well clear to win as she pleased by 14 lengths at 7/2 from 5/1. Our Miss Power (16/5) took a moderate second with Lizrona (14/1) back in third.

Callaghan, who was riding his first winner over obstacles and first winner for Willie Mullins, said: "The mare travelled everywhere, jumped savage and I was just coming to join Jack (Foley on La Prima Donna) at the second last. Unlucky for him he went down at the second last. I thought I had loads of mare so it would have been a good battle to the line if his mare stood up.

"I gave my filly a slap down the shoulder turning in and she was very fast to go and join La Prima Donna to the second last.

"I was delighted to get the ride on her and I knew I wasn't going to be too far away. I gave her a school yesterday morning.

"I'm from Co Carlow, five minutes from Willie. I started off in James Barcoe's and from there I went to Willie's. I'm there about two and a half years. It is a brilliant experience to be there learning every day and riding top horses and riding with top jockeys. You couldn't be in a better place.

"I'm in Willie's full-time for two and a half years and turned conditional three weeks ago and would take outside rides."

Callaghan won a bumper on Jumping Jet for Barry Fitzgerald at Gowran Park in March last year.

Foley was stood down for the rest of the card following his fall.

Additional reporting by Tom Weekes