Arsene Wenger thinks England's European Championship campaign will effectively be over if they lose to France in their opening game next Monday.
The Arsenal manager, who believes his native France could win Euro 2012, also described Roy Hodgson's appointment as a "quick fix" and claims the Three Lions will struggle in Poland and Ukraine due to Wayne Rooney's suspension for the first two games.
England arrived in Poland yesterday with arguably the lowest expectation levels surrounding the national team in recent history.
The controversy that followed Rio Ferdinand's omission, Rooney's suspensions, a spate of injuries to key players, and the fact Hodgson has been in place for a matter of weeks have left the country largely pessimistic about the Three Lions' chances.
Hodgson takes his patched-up team to Donetsk to play their Group D opener against France on Monday and Arsenal boss Wenger fears the Three Lions may as well pack their bags and come home if they lose to Laurent Blanc's men.
"The opening game is England v France and there is no Rooney. You would say that is a game that you can not afford to lose," Wenger told Arsenal's website.
"Why? Not because you cannot catch up, but (because) the pressure inside the country becomes tremendous straight away.
"That game could dictate the whole group. If it's a 0-0 draw, the group is all open, but if someone loses they have a very good chance of going out because Ukraine will beat one of the two, you would say, and Sweden are a hard team to beat.
"They are always well-organised tactically and they have (Zlatan) Ibrahimovic coming back, who can make a difference.
"They are traditionally a difficult opponent for England. It's a difficult group overall."
Hodgson took charge of England two weeks ago after beating the bookmakers' favourite Harry Redknapp to the job.
Wenger admires the former Fulham and Liverpool manager, but admits he is facing an uphill battle to build a team capable of progressing from their group and going far in the tournament.
Wenger added: "England have no Rooney, they have a new manager and they have not worked together so... it's a quick fix.
"Can it work or not? The first game will be a good indication.
"England do have an advantage as Hodgson has managed national teams before, has good experience of tournaments and knows the English players well. It's not unknown territory (for him).
"At the moment England struggle to find confidence and unity and if he can manage to do that he can do very well."
England and France both suffered disappointing World Cup campaigns two years ago. Germany thumped Fabio Capello's men 4-1 after they limped through the group stage, while France revolted against their former coach Raymond Domenech and ended bottom of a group they were largely expected to walk.
Blanc has turned around Les Bleus' fortunes since replacing Domenech, leading them through an unbeaten qualifying campaign that has brought the best out of the likes of Yoann Gourcuff, Karim Benzema and Loic Remy.
Wenger admits the South Africa episode has not been forgotten, but still believes France are capable of winning Euro 2012.
"France has the players to win this tournament," Wenger said.
"But they have not got the confidence and have no certainty.
"South Africa is still inside the team a little bit. Expectation levels in France are low because the scars are still there, but they have the quality.
"They have Benzema, (Franck) Ribery, (Samir) Nasri.
"If they can gel well and they can be psychologically comfortable, they can be a surprise at this tournament."