England all-rounder Stuart Broad will be given as much time as possible to prove his fitness for tomorrow's Champions Trophy semi-final against Australia.
A scan before practice this morning revealed a minor tear in his left buttock and although he bowled at full capacity in the nets at Centurion, he is restricted in certain movements.
"He's got a little tear in one of the muscles in his buttock and we are going to give him a little bit more time to see if he's going to be fit," said England coach Andy Flower.
"We gave him a fitness test out there - he bowled at full pace in the nets but there are other factors like bending, running and fielding.
"He's not 100% fit at the moment but we want to give him a chance."
Having begun a series of exercises under the supervision of physio Kirk Russell and doctor Mike Stone at around 11.45am, the 23-year-old halted midway through one of them and hunkered down with hands on knees.
He flexed his left leg moments later but was clearly unhappy with something.
The group in the middle of the ground were joined by captain Andrew Strauss and Flower at midday.
Following further discussions between the collective, a bat was brought into the middle at 12.10pm and Broad simulated running between the wickets with three shuttle runs.
However, he did not appear to be moving freely and he left for the dressing room with Russell and Stone as the group broke up.
Broad complained of tightness in the buttock during the Group B defeat to New Zealand on Tuesday night, when he claimed four wickets.
So, following treatment yesterday, he was dispatched for the scan first thing this morning while his team-mates began their net session.
Broad was man of the match in the Ashes-sealing win at The Oval in August and his absence for the day-nighter tomorrow would be a serious blow to England's chances of winning a global event for the first time.
Wicketkeeper Matt Prior took part in practice following a virus and whether he can participate in the match will be decided in the morning.
England have International Cricket Council permission to call in stand-by wicketkeeper Steve Davies if Prior is still struggling.
"He's over the worst of that illness," said Flower. "He's still nowhere near 100% though.
"We have had a chat to the ICC about replacing him in the squad and the protocols involved."