Early years
From Standerton to Craven Week
Jacobus Albertus Kriel was born in Standerton, Mpumalanga, on 21 August 1989. At Hoërskool Standerton he served as head boy, captained the first XV, and represented his province at Craven Week — the long-standing showcase for the country's best schoolboy talent. From there he joined the Golden Lions set-up while studying at the University of Johannesburg, where he also turned out in the Varsity Cup.
Rugby career
A Lions cornerstone, a Springbok flanker
Jaco established himself as one of South Africa's most explosive loose forwards during the Lions' run of three consecutive Super Rugby finals. His turnover work and relentless energy earned him a Springbok call-up, and he made his Test debut from the bench against Ireland on 25 June 2016 at Nelson Mandela Bay Stadium — becoming Springbok number 874. He went on to earn 11 Test caps for South Africa.
A move to Gloucester in the English Premiership followed, before he returned to Johannesburg to finish his career where it began. He played his final match for the Lions in April 2023 and retired from professional rugby.
Personal life
Marriage to Nastassja Ras
In 2025, Jaco married South African television and social-media personality Nastassja Ras. The couple's engagement was announced earlier the same year, following a sunset proposal in Santorini, Greece, with the wedding itself taking place in late 2025 and warmly covered by South African media including Top Billing.
Nastassja is one of the most recognised faces in Afrikaans media, and the pair have become a much-loved couple in the South African public eye. They support each other's work — Jaco through the Foundation, and Nastassja through her broadcasting and content career.
Today
Founder, speaker, mentor
Since retiring, Jaco has channelled his energy into the JK6 Foundation — visiting schools across South Africa to share what rugby, injury, comeback, and life have taught him. Every story is paired with practical, evidence-informed tools learners can take home with them.
Book Jaco for a talk