John Kirwan has been appointed Barbarians coach for the club's match against Australia at Twickenham on November 1.
The Blues coach will also direct the team for a game against Leicester Tigers at Welford Road on November 4.
Kirwan said he wanted to provide Australia with a test-type examination before they take on World Cup pool rivals England and Wales as well as facing France and Ireland.
"In my view it's the first test of their tour," he said of the Wallabies. "That's what they'll be expecting and that's what we want to deliver.
"It's a privilege and a huge honour to be involved with the Barbarians again.
"I grew up watching the Barbarians score the greatest try ever and for them to survive and continue to thrive in the modern market place is so important. What they do is a very precious thing.
"Every year the Barbarians are put under pressure but it's still a huge honour to play and they still compete with the very best.
"If you've played for club and country but haven't played for the Barbarians you're still missing something, and when people find out you're the Barbarians coach they're on the phone asking to play."
The Barbarians will name the rest of their squad in the coming weeks before assembling in London on October 28.
Former Wales lock Phil Davies will coach the Barbarians later next month when they face the Combined Services at Bath on November 11.