In what sport do competitors play four racket sports?

Racketlon is a combination sport in which competitors play a sequence of the four most popular racket sports: table tennis, badminton, squash, and tennis. It originated in Finland and Sweden and was modeled on other combination sports like the triathlon and decathlon.

One set is played in each sport, in the order from the smallest to the biggest racket. Each of the four sets are played with running score to 21 points, with a margin of two points needed to finish a set. In team competitions, however, the individual matches are played to 11 points.

Each player serves two serves at a time, and except in table tennis, this is always one serve from the right side and one serve from the left side of the court. Lots are drawn to decide who starts serving in table tennis, and this player will also start serving in squash.

The winner of a racketlon match is the player or doubles pair who has won the most points in total. When a player leads a match with more points than there are points left for the opponent to obtain, the match is over.