Back injury healing well - Clarke

Michael Clarke is confident his latest back injury is improving but Australia cannot expect him to take much of a bowling load if he plays next week's first Test. Clarke was ruled out of Australia's only warm-up match, which started in Potchefstroom on Friday, and while his team-mates toiled in the field he batted in the nets and ran for the first time on the trip.

"It's getting there slowly," Clarke said after play. "I had a good bat today. Since arriving in South Africa it's improved slowly every day. I'm getting plenty of treatment from the physio, I'm working into more batting every day. Hopefully I'll be able to have a bit of a field, a bit of a run around tomorrow morning after the boys do their warm-up."

Clarke, 27, has had ongoing back problems in the past but this injury is a new and unrelated one. It means that there is a little bit of uncertainty about his recovery time but he said there had been definite signs of improvement.

"I've had a lot of inflammation and spasm," Clarke said. "The spasms have stopped, it's still a little bit inflamed. It's definitely calming down. It's completely different [to my previous injury]. It's a different area. It's higher up in my back, it's sort of behind my ribs, so I get it across and it comes into the front of my chest."

Clarke will not do any net bowling before the first Test, making Australia's spin selection all the more important. The legspinner Bryce McGain was attacked relentlessly by the South African Board President's XI on the first day and finished with 2 for 126 from 19 overs, while Nathan Hauritz was rested.

"There wasn't much spin out there for Bryce today, on a very flat wicket and fast outfield," Clarke said. "I don't think he should take too much from the result. I think he'll be happy that he's bowled a few overs, got a few overs under his belt and hopefully if he gets the opportunity, will look forward to the first Test."

The fast men were a little more difficult to dominate, particularly the impressive Ben Hilfenhaus, who bowled better than his 1 for 60 from 20 overs suggested. He entered the match as the fast bowler least likely to play in Johannesburg - Mitchell Johnson, Peter Siddle and Doug Bollinger were the incumbents from the Sydney Test against South Africa - but finished the first day as the pick of the attack.

Clarke said the most important thing was for an unfamiliar group of bowlers to find some rhythm working as a unit. With the exception of Johnson, the rest of the seam bowlers have a combined experience of six Tests and they are the ones who will be charged with taking 20 wickets in each Test as the Australians aim to cling on to their No. 1 ranking.

"It was again another good opportunity for all the bowlers to play together," Clarke said. "There's not too many Test matches under their belt, apart from Mitch (Johnson). The rest of the guys have played a handful between them so any opportunity you get to bowl as a unit - and that's all the bowlers in the squad - is going to be good for us."