NEWCASTLE UNITED are set to be without Danny Simpson for up to four weeks, but the extent of Fabricio Coloccini's muscle injury remains unclear.

Simpson hobbled off during Sunday's draw with Aston Villa at St James' Park with a hamstring complaint and there were fears he could be out for a number of months.

However, having undergone scans at the club's training base this week, the defender revealed the injury wasn't bad as first feared, although he will still miss three to four weeks.

Defensive team-mate Coloccini has also given Magpies boss Alan Pardew an injury scare after he limped out of a training session while on international duty with Argentina.

The skipper reportedly suffered a muscle strain, which forced coach Alejandro Sabella to call in reinforcements ahead of their World Cup qualifiers against Paraguay and Peru this weekend.

The Magpies were frantically trying to find out the extent of Coloccini's injury yesterday, but the fact the former Deportivo La Coruna man has remained with the squad suggests it could be a minor problem.

That said, Pardew will want his skipper fit when he returns to Tyneside next week given the fact Ryan Taylor and James Perch are also sidelined along with Simpson.

Although the right-back revealed the injury was better than first anticipated, he could miss up to five games including key trips to Everton, Maritimo and Manchester United.

"It's a lot better than I first thought," Simpson told nufc.co.uk.

"I've never had a hamstring problem before. I just felt something bad and I knew straight away I would have to come off.

"But the scan results came back on Wednesday and it is hopefully three weeks, maybe four maximum. It depends on each person their body and how quickly they recover, but it's a lot better than what we first thought.

"Already I'm walking easier than I was on Sunday, so that's a good sign."

Simpson played almost every game for the Tynesiders last season, making 40 appearances in total, and he admits being out on the sidelines isn't something he is used to.

He said: "Injuries are part and parcel of being a footballer, but I'm not used to it - I haven't had many injuries.

"With there not being a game for two weeks, if there is a time to have a little niggle then it's probably now.

"I will just have to see how it is at the start of next week and take it from there, but hopefully I won't miss too many games."

Pardew will hope Coloccini, Simpson and Perch return sooner rather than later, but the Magpies boss has also admitted his side must be stronger at the back.

Last season, the Magpies were particularly impressive at the back, but already this term Pardew has seen plenty room for improvement after the disappointing draw with Villa at the weekend.

"The set plays were awful (against Villa). That's why it was frustrating for a coach. We weren't hitting the areas," Pardew said.

"We're not brilliant from corners. Our record suggests we haven't got great assets to score from corners. We're not proficient.

"As far as I'm sitting here now, I still feel we've had a decent start. We've had tough games.

"We have to take four points and qualification (for the Europa League group stage) and say okay, we need to up it a gear."