Blues coach Sir John Kirwan is expecting Friday's fixture against the Reds to be the biggest challenge of season thus far.
The 2011 champions are in fine form, toppling last year's champs the Chiefs a fortnight ago before grinding out a 19-all draw with the table topping Brumbies last week.
"They're the best side in the competition," said Kirwan. "I thought it was a really tense, physical battle the other night against the Brumbies so we need to be ready for that.
"It's going to be a battle up front firstly because they're really aggressive at the ruck and then we need to try and contain two world class backline players in Will Genia and Quade Cooper."
Kirwan believed the impressive form the Australian teams are currently showing could be attributed to the looming Lions tour.
The Aussies have scored seven victories over New Zealand teams this season, with the Hurricanes the only team to manage a win against them.
"It's a bit like the World Cup isn't it? Everyone has a bit of an edge and wants to be selected. I know when I was playing, to play the Lions was a highlight," Kirwan said.
"I just wish Wallabies coach Robbie Deans hadn't left Quade out of that squad, since then he's been playing the house down."
Captain Ali Williams missed training with an ongoing knee issue but will be fine to take on the Reds, while Kirwan intimated that All Black veteran Keven Mealamu would continue to make his impact felt off the bench on Friday.
"Keven will probably play off the bench. Kevvie's going well and so is JP (James Parsons) so we've got a really nice bit of competition there.
"We know what Kevvie can bring us but JP has also been playing the house down so off the bench for Kevvie and see what happens."