Play against Master and King 
Successfully complete arcade mode using no continues and without losing a round on the normal difficulty setting to play against Master in singles and Master and King in doubles. This can be easily done if the match is set to one round. 

Play as Master 
Defeat Master in singles in arcade mode to unlock him in arcade and training modes. 

Play as King 
Successfully complete all 22 trial and 24 training levels in world circuit mode to reach the number one ranking and have King challenge your player. Defeat King to unlock him in arcade and training modes. 

Underarm serve 
To do an underarm serve, press A + X + Down while at near court, or A + X + Up while at far court. 

Sunflower costume 
Successfully complete the big wall training level with at least ten seconds left on the timer to unlock costume No. 22. 

Tambourine costume 
Successfully complete the bull's-eye training level with a score of at least 7000 to unlock costume No. 23. 

Camouflage costume 
Successfully complete the cannon training level with at least fifteen seconds left on the timer to unlock costume No. 24. 

Zebra costume 
Successfully complete the smash box training level before the timer turns red to unlock costume No. 25. 

Giraffe costume 
Successfully complete the drum shooter training level before the timer turns red to unlock costume No. 26. 

Fire suit costume 
Successfully complete the big ball training level before the timer turns red to unlock costume No. 28.