Pakistan captain Inzamamul Haq is doubtful for the Twenty20 international against South Africa on Friday which precedes a five-match one-day international series starting in Centurion on Sunday.

Vice-captain Younis Khan told reporters on Thursday that Inzamam was still battling the back problem which kept him off the field for most of the last day of the final Test against South Africa in Cape Town last weekend. South Africa won the series 2-1.

"Inzamam was here at training, but he is still struggling with his back problem. It's improving, but he is still only 50-50," Younis said.

South Africa will rest all-rounders Jacques Kallis and Andrew Hall, wicketkeeper Mark Boucher and pace bowlers Makhaya Ntini, Andre Nel and Charl Langeveldt.