Kelly Slater: 11 world titles on his back | Photo: WSL/Kelly Cestari

The World Surf League (WSL) surfers will feature their favorite numbers on their backs. Original idea? Not even close.

Kelly Slater picked number 11 (for the world titles he has won); Gabriel Medina chose 10 (probably the most iconic number in football history), and John John Florence opted for number 12 (ready to beat Slater).

The criteria can be date of birth, favorite digit, lucky number, or any other numeric superstition.

The first time numbers were used in football (soccer) was in the 1920s in England.

Back then, numbers were assigned by field location: for example, goalkeeper, full back, center forward, etc.

In sports, uniform numbers are usually used to identify and distinguish each player from others wearing the same or similar uniforms. They're often seen in jerseys, shirts, or sweaters.

In football (soccer), numbers are traditionally assigned based on a player's position or reputation on the field, with the starting 11 players wearing 1-11 and the substitutes wearing higher numbers. In many cases, players "negotiate" numbers with the clubs.

Interestingly, and despite following the American football business model, the World Surf League is leaving the numbers free for riders to choose from.

The NFL numbering system, for example, is based on a player's primary position.

Shirt numbers are everywhere in sports, from baseball, rugby, cricket, basketball, and ice hockey to racing, cycling, handball, volleyball, and many other professional sports.

Being an individual sport, surfing has no positions except for the one surfers hold in the line-up (priority or no priority).

So, there you go. No rules. Or maybe a single one, apparently because 69 it is not considered a real number by WSL.

The World Surf League Numbers

2015 Men's Samsung Galaxy Championship Tour

2 - Nat Young
3 - Owen Wright
4 - Keanu Asing
5 - Jadson Andre
6 - Wiggoly Dantas
7 - Mick Fanning
8 - Matt Wilkinson
9 - Michel Bourez
10 - Gabriel Medina
11 - Kelly slater
12 - Jonh John Florence
13 - Adriano de Souza
14 - Sebastian Zietz
15 - Italo Ferreira
16 - Kai Otton
15 - Julian Wilson
18 - Ricardo Christie
21 - Adrian Buchan
22 - Kolohe Andino
23 - Jordy Smith
25 - Glen Hall
33 - Bede Durbridge
40 - Jeremy Flores
48 - Bret Simpsons
67 - Adam Melling
77 - Filipe Toledo
81 - Joel Parkinson
84 - Josh Kerr
85 - CJ Hobgood
87 - Dusty Payne
88 - Fred Patacchia
91 - Miguel Pupo
94 - Matt Banting
99 - Taj Burrow
WC - Jack Freestone
WC - Dane Reynolds

2015 Women's Samsung Galaxy Championship Tour

2 - Alessa Quizon
4 - Coco Ho
5 - Nikki Van Dijk
6 - Silvana Lima
7 - Lakey Peterson
9 - Tatiana Weston-Webb
10 - Carissa Moore
11 - Courtney Conlogue
13 - Tayler Wright
16 - Malia Manuel
17 - Sage Erickson
22 - Dimity Stoyle
21 - Johanne Defay
27 - Bianca Buitendag
44 - Laura Enever
88 - Stephanie Gilmore
89 - Sally Fitzgibbons
WC - Bronte Macaulay

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