Mohaather demonstrated a devastating turn of foot to win the Sussex Stakes, the feature event on day two at Goodwood.
Crowley had to switched out to make his challenge, but once he did Mohaather (3-1) fairly flew in the final furlong to collar pace-setter Circus Maximus and score a first Group One win.
Crowley told ITV Racing: "He's an absolute aeroplane.
"Obviously, I wanted to ride him a little bit more forward today - and by doing that, we were in a bit of a pocket the whole way, and got shuffled back, (so) he's done it the hard way.
"He's had to come round them, and still won well.
"Everything went wrong for him - if I'd sat last, maybe ridden him more confidently, he'd probably have been more impressive.
"This is serious - that race there, you're talking about the best milers in Europe. I wouldn't say he's made them look ordinary, but he won very well."
Tregoning said: "I've had to wait a long time (since Sir Percy, for another Group One).
"We obviously haven't quite had the horses. When we left Lambourn we didn't start with very many again."