Fast bowler Dale Steyn is taking his foot off the throttle in his injury comeback this week as Cricket South Africa heed the medical lessons of the past.

Steyn played his first competitive match in almost a year last Wednesday (November 15), and went on to play two more Twenty20 matches for the Titans in the space of five days. While the 34-year-old came through that burst successfully, he has now returned to Cape Town for the next stage of his rehabilitation and will not turn out for the Titans in their two Ram Slam T20 fixtures against the Dolphins on Friday night.

"We're comfortable with the progress he's making but we don't want to push him too much. We're satisfied that he's getting there," Dr Shuaib Manjra, the head of CSA's medical committee, told Cricbuzz.

The reticence towards pushing Steyn too hard comes from two sources. One is the length of the period that he spent on the sidelines after breaking a bone in his shoulder during South Africa's Test series in Australia last November. The other is recent experience of nudging fast bowlers along in their recovery too quickly, which contributed to a situation during the recent Bangladesh tour when South Africa were missing no fewer than four frontline quicks.

"One of the risks we've found is when there is a sudden ramp-up. If a guy hasn't been bowling much and then you suddenly ramp him up, the risk of injury goes up significantly," said Manjra. "We're concerned about not ramping (Steyn) up too much, so we're allowing him to bowl, then go and rest, and then go back and bowl.

"That's the evidence in the scientific literature as well. The Australians have found it and we have experienced it. But before the international season starts again, they must have sufficient bowling under their belts."

Steyn will spend some of his time 'off' continuing his rehabilitation with a biokineticist in Cape Town, and some of it bowling longer spells in the nets with the view to building his fitness for South Africa's Test season, which begins with the one-off Test against Zimbabwe on Boxing Day.

But while Steyn is on track to make his international comeback in that match, his long-time fast bowling partner, Morne Morkel, is a doubt. Morkel limped out of the first Test against Bangladesh at the end of September with a side strain, and subsequently incurred a back problem that has delayed his return. He is currently being assessed on a "week-by-week basis", according to Manjra, who confirmed that one or two Twenty20 games for the Titans could be enough for Morkel to prove his fitness ahead of the Zimbabwe Test.

However Morkel's brother is not hopeful.

"According to my information, Morne will only be back for the playoffs of the T20 tournament," Albie Morkel, who captains the Titans, said in Pretoria on Wednesday. "He won't be back earlier and I doubt he'll actually be considered for selection given that it will be so late."

Two other Titans players on the injury list are all-rounder Chris Morris and Proteas captain Faf du Plessis. While Morris is expected to return with a remodelled action in the coming weeks, du Plessis is busy recovering from both the back injury sustained in the third ODI against Bangladesh and the shoulder surgery that he underwent three weeks ago.

The shoulder problem had been troubling du Plessis for some time. "We had been looking for a gap for Faf to do the surgery and now we've found it. So he's recovering from both but he's doing pretty well," said Manjra, who suggested that du Plessis could lead South Africa against Zimbabwe even if he fails to represent the Titans before the Ram Slam ends on December 16.