BBC Sport's guide to New Zealand's Tri-Nations squad.
Enjoyed instant success on his appointment at New Zealand Warriors, guiding them to the play-offs in three successive years. Resigned in June following a poor season. Replaced Gary Freeman as New Zealand coach in March 2003.
Jason Cayless is one of the fittest players around
NZ Warriors, loose forward or hooker, aged 19, 1 cap
Like his brother Vinnie, a determined defender who averages 40 tackles a game for the Warriors.
NZ Warriors, centre or stand-off, aged 25, 2 caps
Strong line-breaking runner who is a defensive specialist.
Canterbury, prop or second row, aged 22, 1 cap
Arguably the quickest prop in the NRL. Has line-breaking ability and provides very quick play-the-balls.
Sydney Roosters, prop, aged 24, 4 caps
One of the fittest players around. Drops few balls, makes lots of ground-gain and is smart at the play-the-ball.
Parramatta, prop, aged 26, 21 caps
Rarely makes an error and always provides leadership. A rock when the going gets tough.
Melbourne, prop, aged 29, 0 caps
Has helped plug the gap created by the unavailability of Tony Puletua. Made a big contribution to Melbourne's successful season in 2004.
Wests Tigers, centre or back row, aged 21, 0 caps
A surprise late call-up but enjoyed a fine season with Wests Tigers.
Bradford, centre, aged 22, 0 caps
Has formed a highly-effective partnership with Lesley Vainikolo at Bradford. Has been responsible for many of Vainikolo's record 39 tries this year.
Melbourne, centre or second row, aged 27, 8 caps
Never fulfilled his potential at Warrington but a tough tackler who has enjoyed a terrific season with Melbourne. A good support player who has good speed for a forward.
NZ Warriors, second row, aged 24, 0 caps
Played against Great Britain for the Maoris in Auckland in 1999 and has been on the fringe of international selection for the last three years.
Leeds, second row, aged 25, 11 caps
Named in the Super League Dream Team even though he didn't join the Rhinos until May. Has amazing ball skills and takes plenty of stopping.
Leuluai has been linked with Widnes
NZ Warriors, scrum-half, aged 19, 3 caps
Carved the Aussies up on his debut in 2003, setting up several tries. A solid ball delivery combined with an error-free game. Linked with a move to Widnes.
Canterbury, centre or wing, aged 23, 0 caps
Enjoyed a terrific season with the Bulldogs but missed out on the play-offs after picking up an ankle injury. A late call-up for the Tri-Nations Series.
NZ Warriors, wing, aged 25, 11 caps
A blockbusting winger who made his mark on the 2002 tour of Britain. Offers a powerful punch out wide and solid dummy-half work.
Bradford, hooker or half-back, aged 28, 24 caps
Can fill a number of roles. Has appeared most at hooker for the Bulls this year but is best at in either half-back role. Has also played for his country at full-back.
North Queensland, prop, aged 31, 6 caps
One of the few ball-playing front-rowers in the NRL, he missed the opening Tri-Nations game through injury.
Bradford, second row or loose forward, aged 29, 26 caps
Reached the Super League Grand Final in his first season with Bradford to add to his runners-up medal from the 2002 Grand Final with the Warriors.
NZ Warriors, centre, aged 24, 4 caps
Classy centre whose tour in 2002 was curtailed by a broken hand sustained in a late-night punch-up with team-mate Nigel Vagana. Missed the opening Tri-Nations match after undergoing surgery.
Cronulla, centre, aged 29, 22 caps
A proven finisher who topped the Super League tryscoring charts with Warrington in 1997. Brings leadership and a never-say-die attitude. Quick, with a great step and good vision.
Williams is being billed as a star of the future
Bradford, wing, aged 25, 12 caps
Explosive winger who is not nicknamed "the Volcano" for nothing. Capped a wonderful season with his 39th try in the Grand Final defeat to Leeds.
NZ Warriors, hooker or full-back, aged 22, 1 cap
Fast off the mark, a good broken play runner with strength to off-load, who times his support runs well.
Penrith, centre, aged 23, 2 caps
A strong-running centre who came into his own this year with solid performances for the Panthers.
Canberra, captain, prop or back row, aged 31, 40 caps
Carries enormous respect from team-mates and opposition alike. A damaging runner with the ball who can carry half an opposition pack. Hurts when he
tackles. Fearless, tireless and a great on-field leader.
Sonny Bill Williams
Canterbury, loose forward, aged 19, 2 caps
Has size, speed and strength, vision to back up, a great offload and a defensive shoulder charge that flattens opposition props. A true game-breaker.