Cheika will attend the Super Rugby match wearing his Waratahs coach's hat, but the importance of how both No. 8s perform with a view to the bigger picture of Wallabies selection to come won't be lost on him.

Cheika made it clear before the Waratahs captain's run on Friday that his Wallabies coaching hat was back at the Australian Rugby Union office in St Leonards, and that all he was interested in on Friday at the Waratahs' Moore Park bunker was talking about the challenge ahead for the Tahs.

But he spoke openly of Palu, 32, and McCalman, 26, especially the 192cm and 108kg McCalman who he coached during last year's Wallabies European spring tour in which he started at No. 8 against the Barbarians and in all four Tests against Wales, France, Ireland and England,

"They are a different type of profile," said Cheika who as the Waratahs coach understandably has a better knowledge of the 115kg and 194cm Palu who has 54 Test caps, but missed the Wallabies spring tour due to concussion issues.

"Wycliff is a big impact player, but in the same way they are the sort of heart and sole of their team – Wycliff for us and McCalman for the Force."

Cheika then said of Dubbo-born McCalman who played nine of his 38 career Tests last season in a year disrupted by a shoulder injury: "I enjoyed coaching [McCalman] on the Wallaby tour. I thought he was a really interesting guy. He put himself out there for the team, and I enjoy that."

So wary Cheika of McCalman's potential ball running danger on Sunday, he warned the Force backrower to expect some solid marking on Sunday.

Cheika puts McCalman with the Force's centre pairing of No. 12 Junior Rasolea and No. 13 Kyle Godwin as players who could bust NSW's defence.

"It is going to be a challenge and I will be telling my blokes to make sure they nullify [McCalman's] strength in a serious way," Cheika said.

"We are going to have to look after those guys. We are going to have to be aggressive. McCalman can make breaks as can Godwin and Rasolea."

"[McCalman] is an important player to nullify, especially with [injured captain and backrower Matt] Hodgson missing."

Cheika's view of McCalman was echoed by Waratahs captain Dave Dennis.

"Ben is pretty honest footballer. You know exactly what you are going to get," Dennis said.

"He runs hard, tackles hard, works a lot – good work rate around the breakdown.

"He is a bit of a leader in that team without having a 'captain' next to his name.

"He very much leads that forward pack. We expect a solid game from 'Benny' – an in your face sort of confrontation which should be good."

Dennis, who will start in the Waratahs starting second row with Will Skelton, believes the Force: "are a great opponent, first-up" to draw.

Dennis expects the Force's forwards to prove a much needed test for the NSW pack.

"One area we have wanted to improve [on is] our set piece around the scrum and line-out, our maul defence, our own attacking mauling," he said.

"To be tested straight up is going to be good.

"If you look back at the first game here [in Sydney] last year [won 43-21 by NSW over the Force] they drove a lot off from driving mauls through 80 per cent of the ball they got.  We are expecting a similar sort of approach from them."