England have delayed plans for Liam Plunkett to join the squad in South Africa after he suffered a thigh injury.
Steven Finn began the tour but was forced to withdraw ahead of the fourth and final Test at Centurion due to a side strain that has also ruled him out of the ODI and Twenty20 matches that follow.
Yorkshire pace bowler Plunkett was initially called up as his replacement but, after playing two matches for England Lions in UAE, the 30-year-old has strained a muscle in his left thigh.
He will have a further test on Thursday to check on his fitness but was ruled out of the Lions' opening ODI against Pakistan A in Dubai which got underway on Wednesday.
England have already secured victory in the Test series in South Africa after taking an unassailable 2-0 lead in the four-match series ahead of the final game in Pretoria.
Meanwhile, Lions coach Andy Flower suffered a further injury blow after Somerset seam bowler Jamie Overton was ruled out of their series because of soft tissue damage in his foot.
Overton incurred the problem in the Lions' second warm-up match on Saturday and will now return home.
"It is a real shame that Jamie will not take part in this series," said Flower.
"He was one of the better performers in our T20 series win pre-Christmas, and he was starting to really hit his straps on this section of the tour.
"He was going to be a big part of our bowling attack, but he's got some great work done through the winter.
"He can get back to his rehab and pre-season work with Somerset, and they can look forward to a really potent and genuinely fast bowler working with them this summer."
Watch South Africa v England in the fourth Test. Coverage begins on Friday at 8am on Sky Sports 2 HD.