Sven-Goran Eriksson expects to send a ripple of fear across the World Cup when he writes Wayne Rooney's name on the teamsheet tonight.
Eriksson plans to unleash Rooney from the start against his native Sweden in England's final Group B game.
He believes the Manchester United striker is ready to make his mark on the World Cup just over seven weeks after breaking his foot.
"The opponents do not want to hear that Rooney is going to start," said Eriksson. "He is fit and he is on fire again. I don't think anyone wants to meet Rooney. Maybe scared is not the right word but they will be worried about Rooney."
The 20-year-old has been bursting to make his full World Cup debut but the England boss trusts Rooney to keep a grip on his fiery temper.
There will be no special words of caution before the game for a player who can sometimes allow his enthusiasm to spill out of control.
After training in Cologne yesterday, Rooney wanted to stay behind and play in goal as David Beckham practised his free-kicks but was not allowed.
Eriksson said: "Nothing he does surprises me now but I don't want him injured playing goalkeeper!
"He learned a lot during his short career. He has become better at controlling himself.
"You can't take that away from him because that is one of his strengths.
"He has that fire inside him. He is living on the edge."
Massimo Busacca, who will referee tonight's clash with Sweden, was in charge of England's 1-0 defeat in Northern Ireland in September. Busacca witnessed Rooney's volatile nature in Belfast when the striker's frustration boiled over into a row with his own team-mates, including skipper David Beckham.
Eriksson continued: "You cannot worry about that. You always tell them to watch the referee, especially in this World Cup where you can get yellow cards for almost nothing."
Eriksson is confident Rooney's return to the starting XI will provide a boost for players and fans alike. But the Swede was also careful to counter that with a warning that the United star will need time to adjust to the pace of the game.
Eriksson said: "Wayne Rooney is very close to what he can do. But I don't think we should expect too much. Don't expect him to be 100 per cent Rooney and solve everything by himself.
"He needs matches to get the timing.
"He is fit, he can run, he can do everything but it is just those final things he needs to find again and it is coming day by day."