Unlock the following characters by performing the corresponding tasks:

CHARACTER - HOW TO UNLOCK
Boris Becker - Beat arcade mode without losing any points. Defeat becker in the secret tournament.
Duke - Beat king of players and defeat duke.
King - Beat king of players and defeat king.
Stefan Edberg - Complete arcade mode in doubles.
Tim Henman - Beat arcade mode without losing any points. Defeat henman in the secret tournament.