The NSW Waratahs' flatlining Super Rugby season is set for another major blow with inspirational hooker Tatafu Polota-Nau to be ruled out of Sunday morning's (AEST) must-win clash against the Stormers in Cape Town.
The Waratahs are expected to make Polota-Nau's withdrawal official on match eve but coach Michael Foley told AAP he wasn't prepared to risk the Wallabies rake, who is still recovering from two nasty head knocks against the Brumbies a fortnight ago.
Foley said the 26-year-old was close to completing a full recovery but he couldn't afford to throw caution to the wind - even for such an important game.
The absence of Polota-Nau's destructive ball-running and ferocious defence in what will be a highly-physical encounter is a massive loss for a NSW team desperate for their first win on foreign soil in two years.
The Waratahs have enjoyed only one victory in 13 matches overseas in the past three seasons and another loss will realistically end their play-off hopes.
John Ulugia had been bracketed with Polota-Nau and is poised to wear the No 2 jersey with the 31-test hooker now likely to return against the Cheetahs in Bloemfontein next weekend.
''I think he'll only miss (the Stormers match) by a day,'' Foley told AAP from Cape Town.
''We're so close but playing could be a risk to him and we don't want to take that risk.
''People have played with corks and sprains and all sorts of things before but I think it's just so unwise to put people at risk who have had a head knock and they're not 100 per cent right.''
Newlands looms as the toughest of last-chance saloons for the Waratahs with the fourth-placed Stormers boasting a proud home record over the past three years and the best defence in the competition.
But Foley has looked closely at how both the Queensland Reds and Crusaders last year scored upset Cape Town wins and will also aim to play a disciplined and strategic field-position game.
The Stormers kick and back their brick-wall defence to feed off errors and penalties within the opposition half and are renowned for grinding out tight wins.
Foley admitted the trick would be choosing when best to attack as unlocking their set defence was extremely difficult.
''Stats would tell you that over the last two or three years that the better attacking sides have actually lost to them when the defence is set,'' he said.
The Waratahs are also wary of the dual threats of Springbok backs Bryan Habana and Jean de Villiers who are experts at intercepting wide passes.
Habana will celebrate his 100th Super Rugby match at Newlands and has bounced back towards career-best form following a poor 2011.
''Bryan is in exceptional form,'' Foley said. ''He's certainly a guy who sniffs a try out of nothing and one who has to be watched.''
Which two NZ teams look the most likely to make the Super Rugby playoffs?