STEVE McClaren last night insisted England were still on track for the World Cup finals, but admitted Wednesday's humiliating 4-1 defeat to Denmark had been a wake-up call for the entire nation.

The England number two returned to domestic duties with Middlesbrough yesterday morning but, inevitably, his head was still reeling from events in Copenhagen some 15 hours earlier.

Despite shading the first 45 minutes of what started as a low-key friendly, a calamitous second-half saw England ship four goals as they slumped to their heaviest defeat for more than 25 years.

Prior to leaving for the Danish capital, Sven-Goran Eriksson's players were being lauded as potential World Cup winners. On their return, the likes of the under-fire David James and the hapless Glen Johnson were being pilloried as an accident waiting to happen.

McClaren refutes suggestions that this week's defeat places a huge question mark over England's ability to even qualify for next summer's finals in Germany, let alone win them.

But the Boro boss admits the second-half performance was a timely reminder of the work that still needs to be done if the national squad are to live up to their obvious potential.

"It was disappointing - there's no two ways about it," said McClaren. "The second-half performance was one of the worst that I've ever been involved in.

"But it might get everyone's feet back on the ground - the staff, the players and the nation as a whole.

"I'm not saying it's a nice thing to happen to you, but sometimes these things can be used to your benefit.

"It proves how far we've still got to go. We can't rest on our laurels and think we're a good team because Wednesday's game proved there are certain nights when we're not.

"If that had been in a qualifier or during the World Cup, it could have been curtains for us."

While the emphatic nature of the final result was an embarrassment, England's second-half collapse was made all the more baffling by the positive first-half display that preceded it.

The ever-competitive Wayne Rooney had a goal disallowed and a penalty appeal turned down, before the wheels came off.

James and Johnson blotted their copybooks with a series of second-half errors and, while McClaren refused to single out individuals, he acknowledged that lessons need to be learned from the disastrous sequence of events.

"What happened in the second half is something we'll have to analyse and look at very closely," he said. "It can't happen again.

"It was strange because, when we met up, the atmosphere was very good. Training was good and we were delighted with what went on in the first half. I thought we could quite easily have been two or three goals ahead at half-time.

"But, while the first half was very good, the second half showed exactly what opponents can do to you if you're not right.

"We haven't got the right to go out and play and think we're one of the best. You've got to prove that.

"We didn't prove it in Denmark, but I'm sure the players will be eager to prove how good they are when we meet up again in two weeks' time."

There will be no room for error when England next take the field, with Wales providing the opposition for a World Cup qualifier in Cardiff's Millennium Stadium on September 3.

Eriksson described Wednesday's defeat as "a disaster" shortly after the final whistle but, after allowing the dust to settle, the Swede promised his side would regain their lost pride next month.

"I can promise you that the qualification games will not look like this," he vowed. "Otherwise, it would be very dangerous.

"Do we need to repay the fans' faith? Yes, of course. But we can put it right and I still have belief in these players. Hopefully this will make the spirit even stronger.

"But that doesn't take away the fact that we can't lose a friendly game like that."

Somewhat inevitably, most of the flak for Wednesday's defeat has been thrown in the direction of keeper James.

The Manchester City custodian, directly responsible for Denmark's opener, lost his first-team place after a costly blunder in Austria at the start of the qualifying campaign and is increasingly being seen as an international liability.

"I have always said that David James was very professional after the Austria game, working very hard and trying to come back," countered Eriksson.

"But after what happened in this game, I don't want to talk about David James or whoever. The second half was a collective disaster. We all played very badly in the second half.

"When you are missing details like attitude, tactics, aggression, not running with the ball or keeping the shape, it became a complete disaster. I will not try to defend anything because almost everything was wrong in the second half.

"I hope the Welsh look at the tape only of the second half. Then their confidence will go up.