Cape Town - Former Griffons flyhalf Jaco Steenberg died suddenly in England over the weekend, reports have confirmed.
The cause of death is still unknown, but according to local website Netwerk24, Steenberg died in his sleep and without having complained of any pain or discomfort.
He was 35.
Steenberg represented the Welkom-based Griffons between 2002 and 2007 before relocating to England, where he played for the Peterborough Lions in the lower tiers of English club rugby.
He moved to Oundle Rugby Club last season.
"Jaco joined the club only last season but his impact on players and team-mates was massive. A genuine rugby man with a great love of the game," the club said on its website.
"Our thoughts and prayers are for his family: Helet, his wife, and son Robert. Please respect their privacy and we will give details of the funeral as soon as we have them."
The report on the Afrikaans website added that Steenberg and his family were due to return to South Africa soon to visit the Kruger National Park.
An autopsy is expected to be carried out on Tuesday.