The NSW Waratahs are preparing for an abrasive Melbourne outfit in their boom or bust Super Rugby AU clash in Sydney on Saturday night.

Waratahs defence coach Jason Gilmore says they expect the Rebels to bring the physicality at Leichhardt Oval, with the finals hopes on the line for both sides.

“The Rebels have good line-speed through the middle of the field and they like to be really physical,” Gilmore said on Monday.

“Their forwards like to intimidate and try to get on top of you.

“They try to be abrasive and try to throw you off your compass with how you play.”

The two teams are separated by just a point on the competition ladder, with the Waratahs (15) third behind the Brumbies (23) and Queensland, on 21.

The Waratahs have a final round bye, leaving them just the one match to earn points with the top three teams advancing to the play-offs.

If they lose to the Rebels, it’s season over – missing the finals for the fourth time in five years.

But if the Waratahs win with a bonus point, and deny the Rebels the same, they can earn five points and thus move six points clear, meaning that Melbourne won’t be able to catch them even with a big last-round win.

“The focus for us is do-or-die,” Gilmore said on Monday.

“We need to win this one and be really strong in the game to potentially stay in competition so we will certainly be preparing really well.”

The Sydneysiders hope to have backrower Will Miller available for selection after an ankle injury while centre Karmichael Hunt, who was a late withdrawal for their match with the Brumbies with a hamstring twinge, is a chance.

“We will give him (Hunt) this week to see how he pulls up and make that call at the end of the week,” Gilmore said.

The Waratahs started well against the Brumbies, only trailing them by a point at halftime but the Canberra men ran in four unanswered tries in what turned into a disappointing 38-11 scoreline.