Owners Godolphin have paid £30,000 to supplement Skiffle for Friday's Investec Oaks at Epsom after the filly pleased trainer Charlie Appleby in a Saturday morning workout.
After finishing a promising third on her Ascot debut at the start of the month, the daughter of Dubawi raised her game to win the Listed Height Of Fashion Stakes at Goodwood, a race won by the brilliant Snow Fairy before she secured Oaks glory six years ago.
Appleby said: "She had a quiet week after Goodwood, as we said she would, and she's in good form.
"She did a routine piece of work this morning and we were very happy with her, so she will be supplemented for the Oaks.
"She's a nice filly, she's done nothing wrong and if we can run into a place I'll be delighted."
Skiffle was the only supplementary entry and is among 11 possibles for the fillies' Classic following the confirmation stage.
They are headed by Qipco 1000 Guineas winner Minding.
Runner-up in last weekend's Irish 1,000 Guineas, she is one of five remaining entries from the Aidan O'Brien stable despite the absence of Ballydoyle.
O'Brien can also call on Even Song, How High The Moon, Seventh Heaven and Somehow.
There is another potential Irish challenger in Jim Bolger's Turret Rocks, who was sixth behind Minding at Newmarket.
The list is completed by Hugo Palmer's Architecture, David Elsworth's Australian Queen, the Ralph Beckett-trained Diamonds Pour Moi and Harlequeen from Mick Channon's stable.
