Wellington - Sonny Bill Williams hopes to "bring a bit of joy into a few sad homes" when he plays his first Vodacom Super Rugby match Friday for a Crusaders team cut off from its home by a deadly earthquake.

The Crusaders will play the unbeaten Waratahs in the third-round match at Trafalgar Park in Nelson, more than 400km from their home base in Christchurch where at least 160 people died last week in a magnitude 6.3 quake.

The seven-time Super Rugby champions will play the remainder of their home matches this season at Nelson, a smaller provincial city near the tip of the South Island, because their home ground, AMI Stadium, is damaged and the infrastructure of their city is in ruins.

Williams said that although the Crusaders have been forced to play outside their ravaged city, they hoped that their efforts on Friday - including his own as he returns from a leg injury - would give fellow citizens some solace.

"I'm not going to stand here and say I know what (people in Christchurch) are going through because I did not lose a loved one," said Williams, who quit Australia's National Rugby League before switching to play rugby union in France and ultimately shifting to New Zealand.

"This is definitely a game for the Canterbury people and hopefully it will take their minds off what has been happening around them for 80 minutes. We have to go back to normality and be the big, strong rugby players that we are."

The Crusaders have enlisted the help of noted New Zealand sports psychologist Gilbert Enoka this week to help players cope with the mental strain of the past week.

"Gilbert talked to the guys about the trauma they have been through and I think it really helped refocus us," coach Todd Blackadder said. "(It's) just understanding that it's quite normal to feel stressed."

The Waratahs will be without Wallabies playmaker Berrick Barnes for the important third-round match. Barnes sustained a minor head injury as the Waratahs beat the Reds 30-6 last weekend to continue it's unbeaten start to the season.

Captain Phil Waugh, however, has been passed fit for the match after being thought likely to be sidelined for up to seven weeks with a torn biceps.

Crusaders and All Blacks prop Wyatt Crockett said his team faced a tough task in its mission to lift the morale of Christchurch because the Waratahs were an outstanding team.

"I'd have to say they are probably the form team of the competition," Crockett said. "Their forward pack has been doing a really good job for them, getting some good quality ball and obviously out wide they've got a lot of class.

"They've got threats right across the park."

The clash between the Crusaders and Waratahs opens a round which will be concluded on Saturday by a match between unbeaten teams, South Africa's Bulls and theHighlanders.

The Highlanders have impressively beaten the Hurricanes and Chiefs in their first two matches, while the Bulls have narrowly beaten fellow South African clubs the Lions and Cheetahs.

"The Highlanders did well to beat the Hurricanes in Wellington and you can see they are playing with self-confidence," Bulls coach Frans Ludeke said. "Their ball retention and breakdown play are particularly impressive but, that said, we are looking forward to the challenge. They are also the first overseas team we face, which makes it more exciting for us."

The Bulls' wins over the Lions and Cheetahs were narrow and hard-fought but Ludeke said he was happy with his team's performance under pressure.

"We played against good teams in the last two games and had to work hard to secure those away wins. So even though we know we can play better, it is important for us as a team that we managed to grind out the victories," he said.

Former captain Wickus van Heerden will start at lock for the vastly-improved Lions against the Blues on Friday. The Johannesburg-based Lions, under former All Blacks coach John Mitchell, have started their season with narrow losses to the Bulls and Stormers, last year's Super 14 finalists.

"What impressed me is that we worked together as a team for a longer period (against the Stormers)," Mitchell said. "Eleven of the players only played in their second Super rugby match, and the matches for the past two weekends were against last year's champions and the other finalist.

"We're definitely on an upward spiral."

The Rebels will try to build on their first win in the Super 15, over the ACT Brumbies last weekend, when they meet the winless Chiefs at Hamilton on Saturday. In response to its defeat the Brumbies fired coach Andy Friend and must now overcome the wrenching disruption of that decision before a derby clash with Queensland in Canberra.

In other matches, the mForce meet the Durban-based Sharks at Perth and the Stormers play the Cheetahs at Cape Town.

Teams

Crusaders:
15. Israel Dagg, 14. Sean Maitland, 13. Robbie Fruean, 12. Sonny Bill Williams, 11. Adam Whitelock, 10. Daniel Carter, 9. Andy Ellis, 8. Kieran Read (captain), 7. Matt Todd, 6. George Whitelock, 5. Sam Whitelock, 4. Brad Thorn, 3. Owen Franks, 2. Corey Flynn, 1. Wyatt Crockett

Substitutes: 16. Quentin MacDonald, 17. Ben Franks, 18. Chris Jack, 19. Jonathan Poff, 20. Willi Heinz, 21. Matt Berquist, 22. Tom Marshall

Waratahs:
15. Kurtley Beale, 14. Lachie Turner, 13. Rob Horne, 12. Tom Carter, 11. Drew Mitchell, 10. Daniel Halangahu, 9. Luke Burgess, 8. Ben Mowen, 7. Phil Waugh (captain), 6. Dave Dennis, 5. Kane Douglas, 4. Dean Mumm, 3. Al Baxter, 2. Tatafu Polota-Nau, 1. Sekope Kepu

Substitutes: 16. Damien Fitzpatrick, 17. Benn Robinson, 18. Sitaleki Timani, 19. Pat McCutcheon, 20. Brendan McKibbin, 21. Ryan Cross, 22. Afa Pakalani