Steyn, who did not bowl in India's 2nd innings in the 1st Test in Mohali due to tight right groin, failed to pass fitness Tests at Bengaluru's M Chinnaswamy Stadium.
Today (November 13), Proteas captain Hashim Amla confirmed that his team will be without Steyn in AB de Villiers' 100th Test.
This the 2nd injury blow to South Africa in 2 days. Yesterday (November 12), Vernon Philander was ruled out of the remainder of the series after injuring his ankle during training.
The visitors are trailing 0-1 in the 4-match series. India won the opener in Mohali by 108 runs. The 2nd Test starts tomorrow (November 14).