Magical, the 2018 Breeders' Cup Turf runner-up who defeated males in Ascot's Champion Stakes (G1) last fall, had retirement planned for her after spiking a temperature and missing the 2019 Breeders' Cup.
"Magical is still with us in Ballydoyle," O'Brien said of his stable. "She has done very well physically over the winter and [the Coolmore partners] are considering letting her race on this year.
"She is due to be covered by No Nay Never and a decision about the coming season will be made in the near future."
That could mean more matchups with her main rival, Enable, or the type of campaign that would keep them separated. While Magical has been just short of brilliant in races absent the British champion, she has finished second three times to Enable, including the Breeders' Cup Turf.
Overall, Magical has won nine of 21 starts, also taking the Tattersalls Gold Cup (G1) and Irish Champion Stakes (G1) in 2019, when she ran fifth in the Prix de l'Arc de Triomphe (G1), rated the world's best race.