Croke Park is set for an epic encounter this weekend as Brian O'Driscoll, playing his 100th test, leads Ireland into battle against the Wallabies on Sunday afternoon. Peter Murison previews the big clash.

The reigning Six Nations champions are seen as the Northern Hemisphere's big hope this November and this weekend, welcoming Australia to the historic Croke Park, they have an opportunity to get one over a Tri-Nations powerhouse.

Looking ahead to the clash, O'Driscoll himself says he is still enjoying the challenge of international rugby as much as he ever had and insists that the Wallabies pose a unique challenge for any side.

"I enjoy it as much now as I did in the early days, though it probably comes more naturally to me now," said O'Driscoll.

"Australia are a very smart team, the smartest in world rugby. They think about how to break down defences and have the personnel to do that.

"They're able to adapt on the pitch, changing from Plan A if they need to. That makes them dangerous."

Australia overcame England at Twickenham last Saturday, winning 18-9, but were outplayed in the opening forty minutes of the match. Their second half performance certainly warranted the victory but Robbie Deans' coaching staff would not have left London too satisfied with what they had seen.

Last weekend's biggest shining light for the Wallabies was the Man-of-the-Match winning performance of scrumhalf Will Genia. Dictating the pace of the game and showing great strength around the breakdown the Queensland Reds star stole the show.

Other highlights during the match for Wallaby fans were the performances of Quade Cooper and captain Wycliff Palu.

But, while they are confident, Ireland's youthful opponents are equally well aware of the challenge posed by the European champions.

Despite the advantage of playing a Test already this season, and facing a team notoriously sluggish at the outset of the November series, Australia coach Robbie Deans is mindful Irish rugby is going through a golden era at both international and provincial level.

"It's going to be a litmus test for us. They're the grand slam Six Nations champions, European Cup champions two years in 08 and 09 (Munster and Leinster), so there's an awful lot of experience and belief in the group we're playing at Croke Park," Deans said.

But the New Zealander's team have more than their 18-9 victory last weekend against England to give them an edge.

Flank Rocky Elsom played alongside O'Driscoll in the Leinster team that won the European Cup last season and assistant coach Jim Williams played for and coached Munster.

And now Elsom has the honour of captaining the Wallabies against many of his former Leinster teammates.

But with Australia having lost two of their last three Tests in Dublin, Elsom's mood was not especially sentimental.

"I wouldn't say I was really pumped up to be playing against the guys but it will be good to see everyone and catch up.

"This is probably the best Irish side we've ever seen. Definitely it's a big challenge," said Elsom, whose team are bidding to become only the second Australia side after the celebrated 1984 Wallabies to complete a grand slam of wins over England, Ireland, Scotland and Wales on the one tour.

O'Driscoll though said Elsom would concentrate on the immediate job at hand.

"He's a world-class player. I'm sure his mind will be solely focused on winning a Test match.

"I happened to bump into him in a restaurant in Dublin on Monday, we just chatted away for a while.

"But for 80 minutes on Sunday we'll put all that aside and we'll take each other on."

Playing his 100th test, Ireland captain O?Driscoll will no doubt be a marked man once again this weekend. 93 Irish appearances and six Lions appearances, BoD has enjoyed a great 2009 so far and will be hoping to add a couple big Southern Hemisphere scalps to his list this month.

Another Leinster man meanwhile will be making his first appearance for Ireland this weekend. Cian Healy, still just 22 years old, has quickly risen to prominence with the Heineken Cup Champions and will now have his chance to shine on the international stage when the Wallabies come calling.

With Ronan O?Gara retained at flyhalf ahead of Jonny Sexton, Ulster playmaker Paddy Wallace slots into the No.12 jersey. Prefered to Gordan D?Arcy, Wallace will be asked to help create the space for O'Driscoll, Tommy Bowe and Luke Fizgerald exploit.

Australia have made just one change to the team that won at Twickenham with 21-year-old David Pocock pushing openside flank George Smith - one of the ten other players O'Driscoll will join in the 'hundred club' - onto the bench.

Players to watch

For Ireland: British and Irish Lions star Tommy Bowe has had a sluggish start to the new season but remains one of the most exciting players in European rugby at the moment - expect him to take the slightest chance on offer. Any fan of Irish rugby would have seen this debut coming - Cian Healy is a fantastic young talent and could help give the hosts the edge up front.

For Australia: Filling in for Berrick Barnes, Quade Cooper was brilliant last weekend against England. Inter-changing with flyhalf Matt Giteau, Cooper's skills make him a man to watch. Hooker Stephen Moore was hugely impressive during the November series last year but will need another big performance this time around to give his side a fighting chance.

Head-to-head:

All three of the back row positions offer fantastic battles this weekend with the clash between David Pocock and David Wallace perhaps the pick of the bunch - youth versus experience - it's going to be good! Wycliff Palu vs Jamie Heaslip - physical of note; Rocky Elsom vs Stephen Ferris - two vital ball carriers. In the backline there could be an interesting tussle between, the keen to counter-attack, Adam Ashley-Cooper and, cannon for a left foot, Rob Kearney.

Recent results

Jun 2008, Australia 19-12, Colonial Stadium, Melbourne
Nov 2006, Ireland 21-6, Lansdowne Rd, Dublin
Jun 2006, Australia won 37-15, Subiaco Oval, Perth_AUS
Nov 2005, Australia won 30-14, Lansdowne Rd, Dublin
Nov 2003, WC Pool A - Australia won 17-16,Colonial Stadium, Melbourne
Jun 2003, Australia won 45-16, Subiaco Oval, Perth_AUS
Nov 2002, Ireland won 18-9, Lansdowne Rd, Dublin
Oct 1999, WC Pool E - Australia won 23-3, Lansdowne Rd, Dublin
Jun 1999, Australia won 32-26, Subiaco Oval, Perth_AUS
Jun 1999, Australia won 46-10, Ballymore, Brisbane
Nov 1996, Australia won 22-12, Lansdowne Rd, Dublin
Jun 1994, Australia won 32-18, Football Stadium, Sydney

iafrica.com Prediction: The Wallabies will be boosted by last weekend's performance but, even with the disappointment of the Lions tour for many of their players, 2009 has been a great year for Irish rugby. Expect them to be clinical up front and exciting out wide - Ireland to win by six.

The Teams

Ireland: 15 Rob Kearney, 14 Tommy Bowe, 13 Brian O'Driscoll (captain), 12 Paddy Wallace, 11 Luke Fitzgerald, 10 Ronan O'Gara, 9 Tomas O'Leary, 8 Jamie Heaslip, 7 David Wallace, 6 Stephen Ferris, 5 Paul O'Connell, 4 Donncha O'Callaghan, 3 John Hayes, 2 Jerry Flannery, 1 Cian Healy
Replacements: 16 Sean Cronin, 17 Tom Court, 18 Leo Cullen, 19 Denis Leamy, 20 Eoin Reddan, 21 Jonathan Sexton, 22 Keith Earls

Australia: 15 Adam Ashley-Cooper, 14 Peter Hynes, 13 Digby Ioane, 12 Quade Cooper, 11 Drew Mitchell, 10 Matt Giteau, 9 Will Genia, 8 Wycliff Palu, 7 David Pocock, 6 Rocky Elsom (captain), 5 Mark Chisholm, 4 James Horwill, 3 Ben Alexander, 2 Stephen Moore, 1 Benn Robinson.
Replacements: 16 Tatafu Polota Nau, 17 Matt Dunning, 18 Dean Mumm, 19 George Smith, 20 Luke Burgess, 21 Ryan Cross, 22 James O'Connor.

Date: Sunday, November 15
Venue: Croke Park, Dublin
Time: 15.00 (15.00 GMT; 02.00 AEST, Monday, November 16)
Expected Weather conditions: While heavy rain is expected on Friday, Saturday is set to be sunny with a maximum temperatute of 10?C.
Referee: Jonathan Kaplan (South Africa)
Assistant referees: Christophe Berdos (France), Andrew Small (England)
TMO: Geoff Warren (England)