Three of the top four referees in Vodacom Super Rugby this year have come from South Africa, confirmed by SANZAR's announcement that Craig Joubert of South Africa and Steve Walsh (Australia) will referee the semi-finals this weekend.

Joubert, who refereed the Rugby World Cup Final in Auckland last year, has been appointed to referee the all-New Zealand semi-final in Hamilton between the Chiefs and the Crusaders on Friday morning (SA time).

Walsh will be the man in the middle when the DHL Stormers host The Sharks at DHL Newlands in Cape Town on Saturday afternoon.

This follows on the past weekend where two South African referees took charge of the qualifiers - Jaco Peyper oversaw the Crusaders' 28-13 victory over the Vodacom Bulls in Christchurch and Jonathan Kaplan was the referee when The Sharks eliminated the Reds by 30-17 in Brisbane.

"The four best referees have been selected on their performances this season for the Finals Series," said Lyndon Bray, SANZAR Game Manager. "The two best performing referees are now selected for the Semi-Final matches, and in the first instance they will go head to head for the Final.

"If the form of one referee who refereed the Qualifying Finals is considered on review to be better than the semi-final referees, then they are still considered in the mix for the Final."

Kaplan will be one of the assistant referees in Hamilton on Friday, while Peyper and Marius Jonker will assist Walsh in Cape Town. Shaun Veldsman is the television match official.

Bray said: "The coaches are part of our decision-making process at this time of year, and since 2009 we have had their support for ensuring that we select our best referees on merit, rather than based on neutrality," said Bray.

"The coaches have been an integral part of endorsing the appointment of our referees in the Super Rugby Finals Series."

Match official appointments - 2012 Vodacom Super Rugby semi-finals

Chiefs v Crusaders

Date: Friday, 27 July, 2012

Venue: Waikato Stadium, Hamilton, New Zealand

SA kick-off time: 09h35

Referee: Craig Joubert (SA)

Assistant referees: Jonathan Kaplan (SA), Keith Brown (NZ)

TMO: Garratt Williamson

DHL Stormers v The Sharks

Date: Saturday, 28 July, 2012

Venue: DHL Newlands, Cape Town, South Africa

SA kick-off time: 17h05

Referee: Steve Walsh (Aus)

Assistant referees: Jaco Peyper, Marius Jonker

TMO: Shaun Veldsman