Cape Town - The worry on Proteas coach Ottis Gibson's face was clear to see as Dale Steyn left the field at the Wanderers on Saturday with what looks to be another shoulder injury.
The 35-year-old got through 10 overs in Pakistan's first innings of the third Test, but during his final over he began clutching his right shoulder.
It is, of course, the same shoulder that he broke during the 2016 tour of Australia. That injury kept him out for a year.
As he walked off the field and down the Wanderers tunnel, Steyn smashed the advertising boards in frustration.
He had seen two catches dropped off his bowling on Saturday morning to leave with figures of 0/15.
While an injury to Steyn would obviously be a concern for South Africa in their endeavours to win the third Test, the bigger picture of this year's World Cup is more significant.
Steyn, South Africa's all-time leading wicket-taker in Test cricket, is expected to lead the Proteas attack at the tournament before retiring from ODI cricket after its completion.