09/10/2015 8:05 AM AEDT | Updated 15/07/2016 12:50 PM AEST

Rugby World Cup: Wallabies Select Rookie Of The Year To Replace Hooper

Dan Mullan via Getty Images
BIRMINGHAM, ENGLAND - SEPTEMBER 27: Sean McMahon of Australia runs in to score his side's first try during the 2015 Rugby World Cup Pool A match between Australia and Uruguay at Villa Park on September 27, 2015 in Birmingham, United Kingdom. (Photo by Dan Mullan/Getty Images)

Michael Cheika has made three changes to the Wallabies line-up to face Wales on Sunday (Australian time).

The loss of Michael Hooper through suspension has opened the door for young gun Sean McMahon, who has not put a foot wrong in the Test matches he has played, but has been the unfortunate victim of a very good Wallabies line-up which has allowed little room to bring him into the starting team for most of the tournament.

McMahon will slot straight in to Hooper's number seven spot in partnership with David Pocock at number eight. Pocock has also been named to share the vice-captaincy with Adam Ashley-Cooper.

In addition to McMahon, veteran Drew Mitchell has been rewarded for a brilliant run in the match against Uruguay and brought into the starting line-up in place of Rob Horne who is suffering a shoulder injury.

Big man Dean Mumm has also been included with Rob Simmons dropping back to the bench joining a stellar cast in the reserves, underlining the depth with which Michael Cheika has to work.

The big question of the week has been around the fitness of Israel Folau who suffered a slight ankle sprain in the match against England last weekend. But the fullback has made a determined effort to get up for this match and has been named to start.

In selecting this side it has been more a case of spoilt for choice for Michael Cheika rather than one which sees Hooper leaving a big hole in the team structure.

Australia has won ten straight tests against Wales but it will not be underestimating Warren Gatland's team despite the much talked about injury list.

And Wales will be showing the same level of respect, not underestimating any Wallabies team it faces -- no matter who is in the line-up.

Michael Cheika has almost certainly planned for all contingencies and has not be phased by the need to make changes.

In the past 12 months, since taking over as coach, he has restructured this team and realigned its psyche. He knows this line-up that will run out against Wales on Saturday night at Twickenham will be out there to win but he believes the battle will go down to the wire as each team strives for top position at the end of the group stage going into the quarter finals.