Mohammad Asif has been ruled out of the third one-day international against South Africa due to an elbow injury.
The fast bowler will definitely miss Tuesday's game in Faisalabad, and chief selector Salahuddin Ahmed admitted he could sit out the entire five-match series, which is currently level at 1-1.
"Asif has been advised to rest for one more match as he has not made a 100 percent recovery," Salahuddin told Reuters on Monday.
Pakistan are keen not to rush Asif's comeback as they want him available for next month's tour of India.
Asif's fellow paceman Shoaib Akhtar could return for the fifth and final one-dayer of the series on October 29 after serving a 13-match ban.
Akhtar was handed the suspension by the Pakistan Cricket Board after being found guilty of four misconduct charges following an incident that led to him being sent home from the recent ICC World Twenty20.
"Shoaib Akhtar should be back for the final match so we will have bowling options but we don't want to take a risk with Asif's elbow problem," added Salahuddin.