The winner’s stablemates Legal Spin and Saglawy had cut out the early running, and while Red Gerry briefly led on straightening for home, as soon as the seven-year-old Royal Illusion went on, the race was over.
Sent off at 10-1 under her 7lb-claiming jockey, Royal Illusion had eight and a half lengths in hand over Dalton Highway at the line, making it a Cesarewitch double for Mullins, after Stratum struck at Newmarket on Saturday.
Rock De Baune was another two and a quarter lengths back in third and Red Gerry fourth.
Mullins – also on the mark in the Munster National at Limerick with Cabaret Queen – said: “Joey gave her a very cool ride. He’s obviously a talented young guy on the way up and I’ve been hearing only good words about him.
“I didn’t think she would go on the ground. We have a nice team of staying Flat horses and it’s good to make use of them.”
Revealing ambitious plans for his Cesarewitch stars, Mullins added: “Last night I was thinking, ‘what are we going to do now with Stratum?’ – and there is a $2.5million race out in Saudi Arabia.
“He goes on good ground and she goes on good ground. I’d imagine they will go there if they get an invite.
“It’s on February 29 and is not what I need two weeks before Cheltenham, but for that money we’ll have to go.”