Second in two Group Ones on his travels last year in Germany, his only below-par effort came in the Prix de l'Arc de Triomphe.
With a stud career now off limits, Varian hopes to be the long-term beneficiary, starting in what looks a good renewal of a race better known as the John Porter.
"Defoe is in great form," said Varian.
"His owner decided to have him gelded over the winter and I am very much in agreement with his decision, as it should elongate his career and he is a fun horse to have around."
Heading the opposition is the William Haggas-trained Young Rascal, who returned from an unhappy experience in the Derby to land back-to-back Group Three wins towards the end of last season.
Speaking earlier this week, Haggas said: "Young Rascal is an interesting horse this year. He is going to run in the John Porter, then he will be in quite a few staying races.
"We might have a dart at the Yorkshire Cup, though I wouldn't mind taking him back to Epsom for the Coronation Cup.
"I think he might stay a bit further this year. He has run well with cut in the ground and most of his best form is on it, but I'm not convinced he needs it."
Hugo Palmer runs Mootasadir who has made giant strides on the all-weather but now needs to transfer that form.
"He won a Group Three at the end of last season and seems to be going forward. He was very impressive at Kempton, but he has now got to convert that to turf," said Palmer.
"He has only run twice on turf - once at Doncaster, when they had a cloud burst and it was like running a bog which he hated, and once at Newmarket when he ran on very fast ground and Frankie (Dettori) almost pulled him up.
"He needs to qualify for the Melbourne Cup if we are going to go there. He has got some way to go."
Owen Burrows' Laraaib, Hughie Morrison's Melbourne Cup runner-up Marmelo and Mark Johnston's Communique are others with claims.
A huge field of 16 goes to post for the Dubai Duty Free Stakes - the Fred Darling in old money and annually a decent trial for the 1000 Guineas.
At the front of the market is Ralph Beckett's Dancing Vega, an impressive winner of her only start at Doncaster by four lengths.
She is ridden by Harry Bentley, who told Racing TV: "I'm really looking forward to riding her, she's been one I've been looking forward to all winter.
"She was very impressive at Doncaster, did nothing wrong at all, the form has worked out well, too. We're coming into the race in good form so she should put up a good performance.
"I've ridden her at home in a bit of work and she seems in good form, she should take a step forward from this run, which is what Ralph will be wanting."
Richard Hannon saddles Star Terms, third in the Prix Marcel Boussac on her last outing over a mile.
"Star Terms is in great form," said Hannon.
"She'll want further than this in time. She gets a mile and might even want a mile and a quarter in time. It's up the road, though, and she'll have a great chance."
Aidan O'Brien is represented by So Perfect, the mount of Wayne Lordan, who was placed in two Group Ones as a juvenile, once against the colts.
