Lah Ti Dar emerged as a genuine St Leger candidate after making a stunning return to action in the British EBF & Sir Henry Cecil Galtres Stakes at York.
The one-time Investec Oaks favourite, who has been absent since winning at Newmarket in May, turned the Listed contest in a one-horse affair down the long Knavesmire straight.
Lah Ti Dar (4-6 favourite) hit the front two and a half furlongs out with the minimum of fuss and quickly put daylight between herself and her rivals.
She crossed the line a yawning 10 lengths clear of Light Of Joy, who pipped Sun Maiden for second spot.
Gosden said: "She did everything right. She was very ill and very down with herself with a virus, but she's come back in great order.
"Frankie was emphatic she should run in the St Leger, we'll have to speak to the management and we'll see. I'll always listen to what the jockey says, I always do.
"We'll consider that, there's other routes but it's an appealing race for her - a filly fresh in the autumn - and she certainly wasn't having any trouble with the distance there.
"She was very sick, but she now comes very fresh into the autumn.
"There's every reason to suggest she'll stay in training."
David Lanigan said of the runner-up: "That's job done with her. We kept her in training to get black type so she could become a broodmare.
"She was weak last year, she really needed a mile and a half but wasn't strong enough to get it.
"She then won three handicaps this year and we took her to France for a Listed race and I went with my chest out thinking she had a great chance, but she ran no race at all.
"The key to her is ground, she'd run on the M25 she needs it that fast, I just wish Brighton had a Listed race for her.
"I really haven't thought about what next, as it was all about getting her ready for this."
Sir Michael Stoute said of Sun Maiden: "She's a filly with scope and is still coming together.
"I'm not thinking of the Park Hill as a mile and a half is as far as she'll want this year. Hopefully she stays in training."