(Reuters) - Kelly Slater, the greatest professional surfer of all time, said "everything must come to an end" after his final season of full-time competition on the World Tour came to a close with defeat at the Western Australia Margaret River Pro on Tuesday.

Slater's loss to current ratings leader Griffin Colapinto in the Round of 32 meant the 52-year-old misses the mid-season cut that reduces the field of the top tier World Tour by one-third.