An Austin police spokesperson said a 16-year-old suspect, who had ignored a call to pull over, fled and struck the back of the vehicle driven by Wannenburg at an intersection.
“Hard as nails on the field and soft as jelly off it. A gentle giant,” said the Pretoria-based friend who requested anonymity.
“Words fail me. I am battling to accept that Pedrie is no longer among us.
“He was a lekker oke (good guy) who loved his family, his friends and rugby. He did not deserve to die so young and in such terrible circumstances.”
Pedrie Wannenburg’s son is recovering in hospital
Wannenburg and his son, Francois, were flown to hospital where the former Springbok succumbed to his injuries. His son is recovering while his wife and daughter, Isabelle, escaped serious injury.
“If there is a silver lining on this dark occasion it is that the rest of the family escaped death,” said the friend, who knew Wannenburg from his high school days.
Eugene Eloff, a former coach of the Johannesburg-based Lions franchise, said on Facebook: “I am shattered. I have no words. Just heard that my friend Pedrie Wannenburg passed away in a car accident.
“Devastating news. RIP wonderful man. You will be missed so much. My heart goes out to Evette (his wife) and the kids. Keeping you in my heart and prayers.”
Former Ulster team-mate Dan Tuohy told the BBC that “Pedrie was ever-so talented and when he turned it on, wow, he could really play. He just read the game really well”.
The 1.96-metre forward joined the Pretoria-based Bulls franchise in 2001 and later lined up for Ulster, Castres, Oyonnax, Denver Stampede and Austin Elite.
Born in Mbombela (formerly Nelspruit), he made 99 consecutive appearances for the Bulls and played for the Springboks between 2002 and 2007.
He moved to the United States six years ago and was working in the refrigeration industry and coaching the West Houston Lions.
By Garrin Lambley © Agence France-Presse