Australia trade positions with England for the Urn
Jack Leach injury causing odds to swing
Captain Stokes also not fully fit
Australia 2.1411/10 are the favourites to win this summer's Ashes series which begins at Egbaston a week from Friday (16 June).
Last month, England were the favourites at around even odds but blows to their preparations - including spin bowler Jack Leach being ruled out of the series - has seen them drift to 2.486/4.
A drawn Ashes series, which would see Australia retain the urn, is 7.613/2.
Leach injury blow to England
Scans confirmed Leach had a stress fracture in his back after he developed symptoms during England's Test victory over Ireland at Lord's on Saturday.
The spinner has been the only ever present bowler since Ben Stokes became captain, playing in all 13 of England's Tests in that time and taking 45 wickets.
Stokes bowling doubts
England will miss Leach and his absence is one reason why England have switched positions in the Betfair Exchange market in recent weeks.
The other is doubts about Stokes' fitness for bowling.
The England captain did not bowl against Ireland, due to a persistent problem with his left knee.
In fact, at Lord's at the weekend, he became the first captain in Test history to lead his team to victory without batting, bowling or keeping wicket, as England romped to a 10-wicket win.
He said afterwards that he was "definitely on course" to bowl in the first Ashes Test against Australia at Edgbaston.
Doubts remains, however, about whether he will be able to bowl and, even if he does, for how many overs.
Aussies warm-up against India
England have no more matches before the Ashes but Australia are taking on India in the ICC World Test Final from Wednesday.
This summer, Betting.Betfair is the place for Ashes previews, tips and more from our cricket expert Ed Hawkins.