Dr Williams, who played 13 Tests for South Africa between 1971 and 1976, won the Carling Currie Cup three times as a player with the erstwhile Northern Transvaal (now the Vodacom Bulls), in 1973, 1974 and 1975.

The 2.01m tall lock, who was born in Johannesburg on 29 October 1946, made his Bok debut against France in Bloemfontein in 1971 and played his last Test at the same venue, against the All Blacks in 1976.

Dr Williams coached the Bulls to Currie Cup titles in 1987 and 1988, while they shared the trophy with DHL Western Province in 1989. He was appointed as Springbok coach in 1992 – a position he held for five Tests as South Africa made its way back from sporting isolation.

After his Bok coaching stint had ended when he was replaced by the late Ian McIntosh in 1993, Dr Williams returned to provincial coaching and a career at the Northwest University, where he was dean of students.

In 1999, he moved to the family farm in Limpopo, where he farmed livestock and game. Dr Williams was also a former chairman of Agri Limpopo and won the province’s Farmer of the Year award.

“John Williams was one of only six people who played for South Africa and then also coached the Boks after unity in 1992, along with Carel du Plessis, Nick Mallett, Rudolf Straeuli, Allister Coetzee and Rassie Erasmus,” said Mr Alexander.

“He was a tough-as-nails lock and a great lineout jumper, and because of his knowledge of the game, he had a successful career in coaching, although the return to the Test arena in 1992 was a difficult time for the Boks.

“The Bulls teams from the late 1980s carried the hallmark of his coaching and were almost unstoppable as they dominated the local rugby scene for a number of years.

“As a true rugby man who was more of a gentle giant in essence, John ploughed back into the game after he had hung up his boots and he remained a loyal supporter of both the Bulls and the Springboks.

“Our heartfelt condolences go out to his wife Mariana, his children Elmien, Lianie and Boeta from his marriage with Martie, who had also passed away, as well as other family members, friends and loved ones in this very sad time of bereavement.”