Rugby League

Cheat mode:
The following codes assume that the buttons are in the default configuration and may need to be adjusted if they have been changed.

Master code
Press Up, Down, Up, Left, Down, Right, Up(2), Down, Left, Right, Left, Down(2), Up, Left(2), Right(2), Square(2), Left, Down(2), Up, Circle at the credits screen to unlock all FMV sequences, teams, grounds, and special features.
kiwikid.

Mech players:
Press Left, Right(3), Down, Up, Down, Circle, Square at the "Join Team" screen.

Legionnaire players:
Press Down, Left, Down, Right, Down, Up, Square, Circle at the "Join Team" screen.

Roman Colosseum stadium:
Press Down(2), Up(2), Right, Left, Right, Left, Square at the "Match Settings" in single game mode.

Big heads:
Pause game play, then press Up(2), Right, Down, Left, Right(2), Circle, Square.

Small heads:
Pause game play, then press Circle(2), Down(2), Square(2), Up, Left, Down, Right.

Production stills gallery:
Accumulate one hour of game play. Note: Games with no human players do not add to this time.
Trent Slatter.

Behind the scenes FMV sequence:
Accumulate three hours of game play. Note: Games with no human players do not add to this time.

Alternately, proceed to round 10 in NRL 2003 to unlock a behind the scenes video in the extras menu.
Benjamin Strathie.

Canterbury Bulldogs vs. Paramatta Eels game footage:
Accumulate seven hour of game play. Note: Games with no human players do not add to this time.
Trent Slatter.

New Zealand Warriors vs. Canterbury Bulldogs game footage:
Accumulate fifteen hours of game play. Note: Games with no human players do not add to this time.
Trent Slatter.

New Zealand Warriors vs. Canberra Raiders game footage:
Accumulate thirty-one hours of game play. Note: Games with no human players do not add to this time.
Trent Slatter.

St. George Illawarra Dragons vs. North Queensland Cowboys game footage:
Accumulate sixty-three hours of game play. Note: Games with no human players do not add to this time.
Trent Slatter.

Season highlights FMV sequence:
Accumulate ninety-four hours of game play. Note: Games with no human players do not add to this time.
Trent Slatter.

Cheerleaders FMV sequence:
Accumulate one hundred and twenty seven hours of game play. Note: Games with no human players do not add to this time.
Trent Slatter.

World Club Championship series:
Win the Grand Final of the English Super League as the Bradford Bulls, Castleford Tigers, Halifax , Huddersfield, Hull FC, Leeds Rhinos, London Broncos, St Helens, Wakefield Trinity Wildcats, Warrington Wolves, Widnes Vikings, or Wigan Warriors. Note: Your team must be human controlled in all games.
Trent Slatter.

State Of Origin series:
Win the Grand Final of the Australian National League as the Brisbane Broncos, Canterbury Bulldogs, Canberra Raiders, Cronulla Sharks, Manly Sea Eagles, Melbourne Storm, Newcastle Knights, New Zealand Warriors, North Queensland Cowboys, Penrith Panthers, St. George Illawarra, South Sydney Rabbithos, Sydney City Roosters, or Wests Tigers. Note: Your team must be human controlled in all games.
Trent Slatter.

International teams:
Win the World Club Championship as any English Super League or Australian National League team. Alternately, win the State Of Origin series as Queensland or New South Wales. Note: Your team must be human controlled in all games.
Trent Slatter.

City Vs. Country match:
Win the World Club Championship as any English Super League or Australian National League team. Alternately, win the State Of Origin series as Queensland or New South Wales. Note: Your team must be human controlled in all games.
Trent Slatter.

Tri Tasman and Tri Nations series:
Win the State Of Origin series as Queensland or New South Wales. Note: Your team must be human controlled in all games.
Trent Slatter.

League God difficulty:
Win the State Of Origin series under the Legend difficulty setting.
George Kahwaji.

Sidhe team:
Win the Tran Tasmin International series under the Legend difficulty setting. Then, look under custom teams in single game mode to find the Sidhe team. Each member has a "10" for all stats, making them the best team in the game.
George Kahwaji.

Distract kicker:
When the CPU's team is taking kicks at goal, press R1 + R2 + L1 + L2. This should detract the kicker, and he will miss a lot of the goals, even if they are in front of the goals.
Michael Boyle.

Hint: Announced created player name:
Make a created player with a last name that is the same as a regular player(the first name does not matter). When you play a match and he gets the ball, the game will announce his name instead of the number/position.
Aldino69.

Hint: Strange credits:
Watch the credits until the end. Wait at this screen and a recipe for duck and a sauce will appear. Keep watching after this has ended and "Whoa! Ducks!" will appear.
steve wicks.

Hint: Penalties:
When you are given a penalty and have the choice to punt or kick for goal, choose to punt. Do not press Circle. Your player will just stand there and waste time. This is useful for if you are winning.
Anthony.

Glitch: No sin bin or send off:
To avoid being sin binned or sent off, when a player has caused a penalty that looks like they could be sin binned, pause game play during the replay. Take note of that player's number. Interchange the player before the replay ends and it will say that they have been sin binned/sent off, then it will say they have been interchanged. By doing this, you can keep thirteen players on the field at all times. If you wish, you can substitute them back on before the punt for touch is taken and they will not miss a play. Note: This will not work if they are closer than 20 meters to the goal line.
Da Rammo.