The clash not only signifies a chance for the Waratahs to keep their season alive but no doubt will be one of the most salivating back-row battles of the year.

In the blue corner there's Hooper, Ned Hanigan and Michael Wells up against a formidable trio of Wallabies in McMahon, Lopeti Timani and arguably the competition's form No.8, Amanaki Mafi.

McMahon has forged a reputation as one of the most damaging ball runners in Australia, with the 22-year-old understood to be tempted by a $1 million-a-season offer from Japanese rugby.

After a run on the bench last week, McMahon returns in the No.7 jersey following a long lay-off from injury, however his opposite number has a plan to limit his impact.

"Take his legs mate," said Hooper when asked how NSW planned to stop McMahon. "He's got good leg drive. He's a really quality player. He keeps getting up and it's not only him, it's the rest of their back row with Lopeti back in.

"They've got a really strong back row. It's about consistently getting them down and not letting them get into the game."

While Mafi has made the fourth-most carries of any player in Super Rugby this year (128), Hooper talked up the underachiever that is Wells, who returns at No.8 for the first time since a start against the Reds three weeks ago.

"Playing with Wellsy this year I've been really impressed with his attention to detail," Hooper said. "There are a lot of little things that he picks up that people don't see. His breakdown stuff is pretty special, particularly in attack that you wouldn't notice."

There is neatness about Hooper's statistics this year. From 10 games, the Waratahs' captain has made exactly 100 carries and 110 tackles, while conceding a penalty every 10 tackles.

Hooper has been more aggressive over the ball in 2017 and, as he does so often, been a "do as I do" leader in what has been an extremely lean year for the Waratahs, which has yielded three wins from 10 starts.

"We need a win to keep the season alive," Hooper said. "There's a long, hard 80 minutes ahead for us against an outfit that has nothing to lose. We know that the start of games are going to be pretty crucial. We know they'll come out swinging and we're excited about that challenge. For the rest of the year we want to get the momentum rolling."

A loss on Sunday almost certainly would put the Waratahs out of finals contention, for they have to travel across the ditch to face the Highlanders and Chiefs, the latter having more than triple the competition points of NSW.

Once again, the weather gods have not been kind to the Waratahs this week. Heavy downpours on Thursday and Friday resulted in a very wet captain's run at Allianz Stadium on Saturday morning.

In almost every home game this year bad weather has been a factor and, given the Waratahs have lost their last four matches in a row in Sydney, it may be cause for some concern.

Hooper, however, said they would have to get on with business even if conditions didn't suit the style of rugby they wanted to play.

"No team wants to play in the wet, however we've had plenty of practice in it this year," Hooper said. "It's been a bit of a theme of our home games, which is unfortunate for the fans. We're hoping it's dry, but if it's not we'll adjust. It is what it is.

"We want to win at home and win for the fans."