Williams is booked to ride the French galloper at both Caulfield and Flemington, but at this stage he believes he is a better chance in the lesser of Melbourne's two major cups.
He rode Dunaden to win last year's Geelong Cup, only to lose the Melbourne Cup ride through suspension.
"He's a lot bigger and stronger than last year," Williams said. "Because his physique changed, they were much happier to run with the 58kg."
One of the most impressive aspects to emerge from Williams' reunion with Dunaden was his belief that the horse still has considerable improvement in him.
And he is expecting to see that produced when he rides him again on Monday. "I was happy with what he did today and I know he's got improvement in him," he said.
Dunaden galloped strongly over 1600m, the last 600m in 37s.AAP
Third declarations for the Caulfield Cup were made yesterday. Forty-one horses remain in the race on Saturday week.
Americain (FR), Dunaden (FR) 58; Jakkalberry (IRE), Winchester (USA) 55.5; December Draw (IRE), Voila Ici (IRE) 55; Southern Speed (AUS) 54.5; Midas Touch (GB), Sanagas (GER) 54; Glencadam Gold (IRE), Maluckyday (NZ), My Quest For Peace (IRE), Niwot (AUS), Seville (GER), Tac De Boistron (FR) 53.5; Brigantin (USA), Lights Of Heaven (NZ), Prairie Star (FR), Precedence (NZ), Secret Admirer (AUS), Sneak A Peek (ITY), Unusual Suspect (USA) 53.
Alcopop (AUS), Ironstein (AUS), Moudre (AUS), Tanby (AUS) 52.5; Folding Gear (NZ), Zabeelionaire (NZ) 52; Gatewood (GB), Ibicenco (GER), Shahwardi (FR) 51.5; Bianmick (AUS), Sabrage (AUS) 51; Dance With Her (AUS) 50.5, Auld Burns (GB), Budai (GER), Excluded (NZ), Fictional Account (IRE), Mr O'Ceirin (NZ), Red Eye Special (NZ), Silent Surround (AUS) 50.