NSW centre Tom Carter says the Waratahs will need to hunt in packs to round up Hurricanes dangerman Ma'a Nonu in Friday night's Super 14 "quarter-final" in Sydney.

There's no room for error for either side, with the winners to advance to - and possibly host - a semi-final and the losers to crash out of the tournament.

Nonu's irresistible form over the past month has been a prime factor in the Hurricanes's surge up the ladder and Carter is seeking assistance from teammates to help stop his powerhouse opposite.

"Traditionally, he hits form late in the season and he's done that again. As you've seen, he's obviously in a pretty destructive place," Carter said on Wednesday.

"It's really difficult to defend against him so it's about minimising what he does.

"Ultimately he's going to break tackles and he's going to make line breaks, but it's (about) just supporting your teammates and I guess minimising (the damage) when those breaks happen.

"It's a big challenge, so we've got a few strategies in place and trying to keep him as quiet as possible is the key."

Carter admitted the daunting prospect of containing Nonu sometimes keeps him awake "late at night".

"He's an outstanding player," he said.

"But if we can work together as a group - that's the important thing because, if you defend in isolation, you'll get punished.

"But if you function together as a backline and defend together, you can certainly nullify him to a certain extent."

Carter's midfield partner Rob Horne will also have his hands full, with Conrad Smith on Wednesday named to return at outside centre after missing the Hurricanes' 44-21 demolition of Queensland in Wellington last Friday with concussion.

"Conrad Smith has been the All Blacks 13 for a long time now, so it's an enormous challenge for Rob Horne and myself," Carter said.

"But Horney's an exceptionally good player and this is why you play football - to measure up against the best.

"Hopefully we can do the job for us."

Hurricanes halfback Piri Weepu is in doubt for the crunch match after suffering an ankle injury at training on Wednesday.

Weepu limped out of the session to have ice treatment and was to have tests to determine the extent of the injury before the Hurricanes fly to Sydney on Thursday.

"Hopefully it is just bruising," coach Colin Cooper told NZPA.

"If it's bruising, he'll be fine. We've got a pretty good medical group."

But Cooper wasn't prepared to risk 35-Test All Black Weepu if he was struggling and had no qualms about reinstating Tyson Keats to the No.9 jersey after a strong season.

Apart from Smith's return, loosehead prop John Schwalger has replaced Jacob Ellison, who drops to the bench.

Hurricanes: Cory Jane, Tamati Ellison, Conrad Smith, Ma'a Nonu, Hosea Gear, Aaron Cruden, Piri Weepu/Tyson Keats, Rodney So'oialo, Karl Lowe, Michael Paterson, Jeremy Thrush, Bryn Evans, Neemia Tialata, Andrew Hore (capt), John Schwalger. Reserves: Dane Coles, Jacob Ellison, Nick Crosswell, Scott Waldrom, Tyson Keats (TBC), Jason Kawau/Willie Ripia, David Smith.

Brought to you by AAP © 2024 AAP