The Joseph O’Brien-trained filly was also the second Group 1 winner in a week for the Gilltown Stud-based sire, whose Maltese Cross won the Grand Prix de Paris on Tuesday.

Bred by Sunderland Holding, Johanna Walsh was purchased by Andrew Cary at Goffs Orby Book 1 for €460,000 on behalf of owner Wells Watson. On her previous start, she had finished just a head behind Earth Shot in the Gr.2 Ribblesdale Stakes at Royal Ascot.

“It was unreal,” said winning jockey Dylan Browne McMonagle of the filly’s facile Irish Oaks success. “She was very straightforward from the get-go and relaxed good. She’s a filly with a lot of gears and put the race to bed in a matter of strides.”

O’Brien added: “It was a huge performance - from the three to the two she really came alive and is a hugely exciting filly for the future. We thought we had a messy enough trip at Ascot and Dylan said she was waiting all way up the straight there, but so did Earth Shot so it was hard to quantify. On that, we thought she was a real live contender and I’m delighted for Wells Watson and Andrew Cary. She has a big pedigree and it’s a pleasure to get the opportunity to train her.”

The time of 2:28.49 was the fastest in the race since Shawanda set the record in 2005 and the fourth fastest in its history.

Sea The Stars is now the sire of 26 Group 1 winners in total.

The same sire-trainer-jockey combination also enjoyed success on Sunday when Star Performer won by two lengths on debut at The Curragh.