The daughter of Oasis Dream put in her best work to take the runner-up spot in the Group One over a mile, just a length and a half behind the winner.
That was her first attempt at that distance after winning both her previous starts over six and seven furlongs.
She will now be put away for the winter and then be prepared for one of the Classics.
"She's come out of the race very well," said Head. "She seemed to stay. She got a bit outpaced - she didn't have a clear run early on - but she when she saw daylight she finished well. I was very happy with her race.
"She won't run again his year. We'll see next year where we go to.
"We'll run her over a mile. Hopefully go for the Guineas or the Pouliches (French 1000 Guineas), one of the two. She's a very good filly."