Unheralded Brumbies flanker Jarrad Butler says to win the Super Rugby title you have to prove yourself against the best – and they don’t come much better than returning Crusaders flanker Richie McCaw.

McCaw’s expected return from a fractured thumb against the Brumbies in Christchurch this Saturday will not only be a big boost for the Crusaders, but an “exciting privilege” for Butler.

McCaw is a World Cup-winning captain who has played more than 100 Tests, has been IRB player of the year a record three times and has won the Super Rugby trophy with the Crusaders on four occasions.

Butler, on the other hand, admits he’s only just beginning to feel comfortable in the Brumbies’ run-on side.

The New Zealand-born 22-year-old has been thrust into Brumbies’ No.7 jersey after the season-ending knee injury to David Pocock in round three, which followed the departures of George Smith and Colby Fainga’a last year.

“Richie McCaw is one of the best flankers ever to play rugby,” Butler said.

“That’s why you want to play. To test yourself against the best.”

There are still question marks hanging over where Crusaders coach Todd Blackadder will play McCaw.

His heir-apparent Matt Todd has been in such strong form at No.7 in the Crusaders’ three-match winning streak that McCaw may either play at blindside flanker or come off the bench.

Regardless, Butler insists the second-plaeced Brumbies game plan won’t change.

“He brings a lot of confidence to the Crusaders, just having him around is a big boost for them,” Butler said.

“But as far as what we’re going to do, it will stay the same.”

Butler moved from New Zealand to Australia when he was 13.

And while he didn’t grow up cheering on McCaw and his Crusaders teammates on a weekly basis, he still had a strong appreciation for their championship-winning style of rugby.

“I grew up in Wellington so I was never fond of them,” he said.

“But I liked watching them. They’ve got really good structure and their work rate is second to none.”