In badminton, what does a black card shown by the referee indicate?

In badminton, a black card is shown by the referee to disqualify a player for serious or persistent misconduct. A disqualified player is removed from the match, and may be removed from the whole tournament.

The card system in badminton (Laws of Badminton, BWF):

Yellow card: shown by the umpire as a warning for misconduct, for example delaying the game, coaching from outside the court at the wrong time, or deliberately changing the shuttle.

Red card: shown by the umpire for a "fault" for misconduct. The opponent is awarded a point (and the service, if needed). A red card follows if a player who has already received a yellow card misbehaves again, or for a serious offence.

Black card: shown by the referee (after being called by the umpire) to disqualify a player for flagrant or persistent misconduct, such as serious bad behaviour towards officials or opponents.

The umpire holds the yellow and red cards, while the black card is shown when the referee decides on disqualification.

Other badminton rules:

• A match is the best of three games of 21 points.
• A "let" is called to replay a rally, for example if the shuttle gets caught in the net during service.
• A "fault" ends the rally in favour of the opponent, for example if the shuttle lands outside the court or the player touches the net.

Cards in other sports:

• Football: yellow (caution) and red (sending off).
• Hockey: green (2-minute suspension), yellow (at least 5 minutes) and red (permanent suspension).
• Table tennis: yellow (warning), yellow and red (point penalty).
• Rugby: yellow (sin bin) and red.
• Handball: yellow (warning), two-minute suspension, red and blue cards.

Why not the other options?

• ✗A warning for misconduct is shown with a yellow card.
• ✗A fault for misconduct (point to opponent) is shown with a red card.
• ✗A change of service is not indicated by a card.