South Africa are to send a top security consultant to Karachi before they make a final decision about whether to play their one-day international there next week.
Officials said South Africa were uncertain about going ahead with the match after bomb blasts in the city killed 139 people last week.
"The South African security consultant will go and check the situation there for himself and report back on Wednesday, after which the South Africans will take a decision on the venue for the final match," Pakistan Cricket Board (PCB) spokesman Ehsan Malik said on Tuesday.
"In terms of what's happening in Karachi at the moment we are concerned," South Africa manager Logan Naidoo told reporters after his team's six-wicket defeat in Faisalabad on Tuesday. "We want guarantees it is safe for the players.
"We (also) want to leave it open until the last minute because we want to play in Karachi. By sending our security consultant to Karachi and getting PCB (Pakistan Cricket Board) security to work with him we are just exploring avenues how to make it safer."
The game could be shifted to Lahore, venue for the first two matches, although such a move could have adverse effects for future tours.
"If the match is shifted we are concerned it could have adverse effects for tours by other teams in the coming months," said Shafqat Naghmi of the PCB.
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