Johannesburg - Morne Morkel picked up a side strain in his final Test for South Africa at the Wanderers on Saturday.
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The lanky 33-year-old left the field after two balls of his 13th over, and Cricket South Africa confirmed that it was the same side strain that he had picked up in last year's series against Bangladesh.
The good news from a South African perspective was that Morkel returned to the field 15 minutes before lunch, with world from the Proteas camp suggesting that he would "push on".
The injury may influence captain Faf du Plessis's decision when it comes to enforcing a potential follow-on.
Morkel was named man-of-the-match when he picked up nine wickets in the third Test in Cape Town, becoming the fifth South African bowler in history to get to 300 Test wickets.