England great Michael Vaughan has declared the hosts "clear favourite" to regain the Ashes because of a "massive" decision to revert to an older Dukes ball, despite Australia boasting an advantage in pace bowling and spin.
While the immediate focus of both nations is on the World Cup, the captains, selectors and backroom staff are also busy preparing for the five Tests in England, beginning August 1.
Australia are well aware that come August, pitches and grounds in England are expected to be drier than they will be in the World Cup, potentially giving the tourists an advantage through their pace attack, and even the spin Nathan Lyon can extract.
However, a move by the England and Wales Cricket Board last week may have nullified this through a decision to not use this summer's batch of underwhelming Dukes cricket balls and revert to a batch from last year or 2017, which had a more pronounced seam and should help England captain Joe Root and his veteran seamers Jimmy Anderson and Stuart Broad.
Vaughan said the potential Australian attack and the return of Steve Smith and David Warner had Australia in a strong position, but the ECB's decision to use an older version of the Dukes ball was massive.
While he tipped England to win the series, he added that there was still plenty of time for the situation to change.
"I now have England as clear favourite to win the Ashes series but there is so much time between now and then that you don't know who is going to be fit on both sides."
Vaughan, who led England to a breakthrough 2005 series win, said the change of ball could ultimately prove to be a telling blow.
"In English conditions, this ball was a massive thing for the [England] team. To use the Duke this year, it's got no seam, it's not been swinging around in county cricket, it comes down to real pace and spin and you would say if it comes down to a pace and spin contest, Australia probably has got the edge," he said on the BBC.
"I think that will be off his [Root's] mind now as an England captain. When you feel that your home conditions are against you, the ball and potentially the pitches, because of the time of the year ... I am sure it will be a lot drier later on in the summer, the fact that he has got the ball - I will go back to 2005, I don't know what year we went back to, but we went back to a batch of balls that we knew were going to swing around - and that gave us confidence.
"I think the fact that they have the ball sorted will give him [Root] confidence but they will also know that this Australian team is very, very dangerous. They have got some pace, they have got some skill and, if the ball is moving around, you look at Pat Cummins, [Mitchell] Starc, Jhye Richardson, Josh Hazlewood, James Pattinson, they have got enough in their armory to bowl England out and it's [a case of whether] England get enough runs on the board, can the Aussies get enough runs on the board?
"That is exactly how the Ashes will be decided - which batting unit can cope and get enough runs on that scoreboard."
Australia have arrived in England and set up camp in Southampton, having spent several days in Gallipoli on a team bonding exercise. Their World Cup campaign will begin in earnest next week, with practice matches against the West Indies, England and Sri Lanka, which should provide a clearer indication of the batting order and final XI for the tournament opener against Afghanistan in Bristol. Judging by the efforts of Pakistan (9-358) and England (4-359) at that venue this week, the County Ground could be a high-scoring venue.
While Australia and England hope to claim the World Cup, the latter for the first time, Vaughan said a deep tournament run could impact on Ashes form, and even lift pressure on England.
"Everything at the minute is about the World Cup. If it goes great and England win that World Cup, you feel they might have a bit of a downward slide from the celebrations and everything surrounding the fact England have won the first ever men's World Cup. Let's hope that happens. You then feel if that doesn't go as well, you feel the pressure will be on to make sure they get a lift from the Ashes team," he said.