Coach Michael Cheika says his NSW Waratahs face a test of character against the high-flying Highlanders on Sunday as Super Rugby's ultimate under-achievers strive to finally live up to expectations.

The Waratahs can lock up a precious home final with victory at Allianz Stadium and stand-in NSW captain Michael Hooper admits the pressure is on to finally deliver for their long-suffering fans.

"It's obviously important. But that's good," Cheika said on Friday.

"We need to learn to play in these types of matches where there's a big consequence so we don't have to change what we're doing.

"So we stay the same, don't panic, just do what we need to do."

Hooper admitted he wasn't sure what the unpredictable and talented Highlanders would throw at the Tahs.

"I'm not too sure how they're going to play. They play different each week," he said.

"Kicking to our back three is a tough thing all the time and they're good at running it back so we're not sure how they're going to come at us.

"It's good that this year we've seen all different styles of defences and attack run at us so we're starting to get versed in various ways of play."

Clearly expecting a torrid battle up front, Cheika on Friday named six forwards on his eight-man bench, with reserve halfback Brendan McKibbin and winger Taqele Naiyaravoro his only backline cover.

Front-rowers Tolu Latu, Paddy Ryan and Jeremy Tilse have all been named, along with Pat McCutcheon, Will Skelton and Mitchell Chapman, who can all fill second and back row positions.

Hooper understands Cheika's thinking.

"Their forward pack sets up great play for their backs. It's the way rugby works," he said.

"They've got a mobile forward pack, they're good at the breakdown, they get a lot of turnovers and their backs play extremely well off turnover ball.

"They have threats all over the park, but hopefully our forwards can really be up for the challenge."

The fourth-placed Highlanders are equal first in the New Zealand conference with the Crusaders but need a bonus-point win to guarantee themselves finals action.