England will begin their final week of preparation before the Test against SA, with injury concerns hanging over two bowlers.

Jimmy Anderson, troubled by a mystery knee problem over the past month, stayed behind in Durban this morning to have a third injection in the joint.

Three scans have so far failed to pinpoint the problem. But Anderson has continued to experience pain in his right knee, and coach Andy Flower admitted this week that some medical advice suggested the fast bowler should be rested from the one-day international series against South Africa.

Instead, Anderson played in each of the three completed matches - starring with a maiden five-wicket haul in Port Elizabeth - as England won 2-1.

Anderson's pace colleague Ryan Sidebottom has been struggling with a side strain - which was due to be assessed again later today or tomorrow.

Durham seamer Mark Davies, who has been impressing for the Performance Programme in Centurion, is to fly to East London as cover for both Anderson and Sidebottom as England prepare for two two-day tour matches against South African Airways XIs.

There is a therefore a degree of uncertainty over England's seam-bowling options for the first Test - which starts at Centurion on December 16.

Attention will switch this week to that match, and England can test their permutations in the two back-to-back fixtures at Buffalo Park.

There is still an air of celebration in the camp at present, however, at becoming only the second country - after Australia - to beat South Africa in an ODI series here.

Man of the series Paul Collingwood was, like his captain Andrew Strauss before him, careful today not to crow too loudly about England's ODI achievements so far - but is beginning to think optimistically about their chances of challenging for a first ICC tournament success at the 2011 World Cup.

"We're miles away at the moment," an initially cautious Collingwood began.

"But if we continue to improve the way we have over the last couple of months, you could do something special.

"Definitely we may have a chance.

"We're starting to become a world-class outfit."

The key element several England players have identified is a 'can-do' team spirit under Strauss and Flower.

"We've got to continue with that togetherness," Collingwood believes.

"Full credit goes to Straussy and Andy Flower and how they've both turned around what was a dismal performance against Australia (in the summer ODI series).

"They've gone away and thought about where we need to improve, and everybody's bought into it.

"We've managed to form a very close-knit and exciting one-day side in a short space of time.

"There's a lot of hard work going on. But there's also a lot of belief."

England know they must still strive for greater consistency - and that the acid test will come in multi-nation events such as the next World Cup in the sub-continent.

"We've shown glimpses that we can be a very good side," Collingwood adds.

"But we've got to win series like this to get the confidence going.

"There's no point just winning the odd game here and there.

"In the end, it's all about winning an ICC tournament. That is what you're always going to be gauged on.

"That's when the real pressure is on. But certainly in series like this, the pressure is very close to ICC tournaments, and this will give us a major confidence boost."

Collingwood's own batting has been a revelation since he realised, belatedly perhaps, that he has a six-hitting ability it was once thought belonged only to an elite in world cricket.

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"The power in the side now looks a lot better than it used to," he notes.

"It's fair to say most of the guys now can clear the ropes pretty easily.

"But at the same time, with Straussy and Trotty [Jonathan Trott] there, we've got a couple of solid guys who can go through the innings and score big runs and be that rock the others can play around."

The athleticism of England's current ODI squad is a major factor too, according to former captain Collingwood.

"'Morgs' [Eoin Morgan] has come in and played some exceptional innings for such an inexperienced guy," he said.

"But the one thing that really excites me, and where you can take wickets, is the fielding.

"It seems to have gone up a notch and makes a massive difference. It builds pressure, and that's a crucial thing in one-day cricket."

The result so far is a heartening victory, to erase memories of that 6-1 thrashing at home to Australia less than three months ago.

In fact, Collingwood rates success in South Africa as second only to England's 2006/07 tri-series triumph in Australia.

"The series from Australia a couple of years ago, from the position we were in, to win that was probably the number one," he said.

"But this is certainly a close second."

He and England must hope their latest high point is a better omen than that win down under - which was followed within two months by an early and ignominious exit from the 2007 World Cup.

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