Bulls head coach Pote Human has extended his contract with the Super Rugby franchise for another year, with an option to renew.

Human was something of a surprise appointment after the resignation of John Mitchell late last year, with Bulls and Springboks legend Victor Matfield reportedly having been the preferred candidate, but he has led the Bulls to four victories from six games for second place on the South Africa Conference ladder.

"It's a massive honour to be entrusted with this role, especially knowing that I have the backing of the people around me," Human said in a statement released by the Blue Bulls Company.

"It's been a good start thus far, and I firmly believe that we are heading in the right direction as a team.

"However, there is a long season ahead with lots of work to be done, and I am excited to get on with things.

"I'd also like to sincerely thank the Blue Bulls Company for believing in me and giving me this opportunity." Blue Bulls Company, in the same media statement, confirmed the signing of Wiehahn Herbst from Ulster.

The prop, 31, played previously for the Sharks in Durban, racking up 40 Super Rugby caps between 2009 and 2014.