"He [Taufeeq] has been advised four to five weeks rest by the doctors," a PCB spokesman told ESPNcricinfo. "The team management is sending him back and requested for a replacement."
Taufeeq had to sit out of the practice match in East London that ended on Monday and the decision to send him home was taken after the results of an MRI. Pakistan's team manager Naveed Akram Cheema confirmed to ESPNcricinfo that Taufeeq did not train this week. Nasir Jamshed played in his place in the tour match and scored two half-centuries, which puts him in line to make his debut in the first Test in Johannesburg from February 1.
Taufeeq has played 43 Tests since making his debut in 2001 and scored 2943 runs at an average of 38.72. He's been part of the XI in Pakistan's previous 18 Tests, since they played South Africa in the UAE in November 2010. During this period, he scored three centuries and five half-centuries. He was also part of the squad that played two Tests in South Africa ten years ago and was Pakistan's leading run-scorer with 280 runs, including a century in Cape Town.
This season in first-class cricket, Taufeeq scored 377 runs from nine matches at an average of 22.17, with two half-centuries.