Honeysuckle has been forced to work harder than she has before to maintain her unbeaten record in the Grade One Irish Champion Hurdle at Leopardstown.

She is the 9-2 second favourite for the Champion Hurdle at next month's Cheltenham Festival behind the Nicky Henderson-trained Epatante at 4-1.

The Henry de Bromhead-trained Honeysuckle claimed her seventh win over hurdles from as many starts on the first day of the Dublin festival on Saturday (Sunday AEDT).

Everything was going according to plan with Rachael Blackmore tracking stablemate Petit Mouchoir into the straight, but Honeysuckle jumped the last awkwardly and lost ground.

She rallied in the run home to beat Darver Star by half a length.

"She's got a massive heart and a massive will to do it," Blackmore said.

"She was really tough and it's a pleasure to be involved with her."

De Bromhead admitted he was worried until she crossed the line.

"She just looked like she got a bit lonely going to the last," he said.

"I had my heart in my mouth coming to the line.

"Rachael is brilliant and I always say that we are very lucky to have her. She's just riding out of her skin and the mare is deadly."