South Africa seamer Vernon Philander injured his left knee while bowling in the nets Saturday but the impressive newcomer is expected to be fit for the second test against Sri Lanka.
Philander, who has taken 24 wickets and four five-wicket hauls in his first three tests, picked up a mild strain of the medial ligament while practicing at Kingsmead and was treated immediately, South Africa team manager Mohammed Moosajee said.
Moosajee added that team management was confident the 26-year-old Philander would be fine for the second test, which starts Monday.
"At this moment in time we are assessing it as a mild strain," Moosajee said. "Tomorrow, once some of the swelling and inflammation goes down, he'll be allowed to bowl and if he bowls without discomfort, he should be OK."
Philander has been an immediate success for South Africa in tests, winning the man of the series award in his debut series against Australia last month.
He took five wickets in an innings in both tests against the Australians and then returned match figures of 10-102 in South Africa's innings victory over Sri Lanka at Centurion a week ago, just his third match.
Uncapped fast bowler Marchant de Lange would be a likely replacement for Philander if he doesn't recover, with left-arm seamer Lonwabo Tsotsobe not yet fully recovered from a side strain.
South Africa leads Sri Lanka 1-0 in the three-match contest and can wrap up its first home series win since 2008 with victory at Kingsmead.