The 27-year-old has flown out to Munich to consult renowned specialist Hans-Wilhelm Muller Wohlfahrt over the problem he picked up in England's 1-0 friendly victory in Austria on Friday evening.

Allardyce is refusing to re-assess the four-to-six-week period his £17million man is expected to be sidelined, although more optimistic noises coming out of Tyneside have suggested he could be back in action within a fortnight.

He said: "We have sent Michael to Germany to see Dr Wohlfahrt in a bid to speed up his recovery from his thigh injury.

"But at this moment in time, we do not see the point in changing our view that we will be without Michael for between four and six weeks.

"If we start talking about him coming back earlier there will be disappointment if he does not.

"However if we can get him back quicker after Dr Wohlfahrt's treatment, then it will be a huge bonus for us."

Whether or not Owen does return earlier than expected remains to be seen, but his absence for any length of time is a blow to Allardyce, the latest Newcastle manager to be forced to do without his star striker.

Owen has managed only 25 appearances for the Magpies in almost 28 months on Tyneside, and just 15 since fracturing a metatarsal at Tottenham on December 31, 2005.

Allardyce thought he had finally broken that hoodoo after Owen's return from double hernia surgery also carried out in Munich by specialist Ulrike Muschaweck in September.

However, his jinx struck once again after just four successive starts for his club, and the fact it happened on international duty made for added aggravation.

Allardyce told the club's official website, www.nufc.co.uk: "It's a big blow for ourselves and Michael when we felt we were moving in the right direction by him training and being available to play every week.

"We were looking to up the match sharpness and fitness, but he has been dealt this severe blow yet again.

"From our point of view, we just have to manage it as quickly as we possibly can to find the best treatment possible.

"We want to bring that recovery period forward as much as we can.

"But at the moment, it's looking like around six weeks and we don't want to predict any less than that."

For just how long Owen is sidelined this time remains to be seen, although his club will not find itself involved in a fight for compensation.

The bulk of the player's £103,000-a-week wages will be covered by the FA's insurers during his lay-off.

Former chairman Freddy Shepherd fought a long battle for compensation following Owen's knee injury at the 2006 World Cup finals when the FA's cover extended to only £50,000 a week.

However, the escalation in players' salaries led the governing body to increase the level of protection to double that level.

Newcastle midfielder James Milner has seen Owen's mental toughness when recovering from previous injury.

"It's a big blow again," said Milner.

"He's come through injury problems and worked so hard to get fit.

"He showed his class when he came back, even though there were a few doubters. It's unbelievable there could be doubters after the quality he has shown over the years and the goals he's scored.

"But he's mentally strong and he will work twice as hard to get back fit again.

"You need to be mentally strong when you're in the gym on your own in the afternoons - it can be tough. I'm sure he'll be scoring for Newcastle and England again soon."