Coaching is considered to be communication, advice or instruction of any kind, audible or visible, to a player.
In team events where there is a team captain sitting on-court, the team captain may coach the player(s) during a set break and when the players change ends at the end of a game, but not when the players change ends after the first game of each set and not during a tie-break game.
In all other matches, coaching is not allowed.
Case 1: Is a player allowed to be coached, if the coaching is given by signals in a discreet way?
Case 2: Is a player allowed to receive coaching when play is suspended?