The South African will make history today as the first man to win four overall titles, confirming his absolute dominance in the annual short-course series.
Tied with fellow South African Cameron van der Burgh with three series titles apiece, Le Clos will add to his series titles from 2011, 2013, and 2014.
Le Clos is undoubtedly the most successful swimmer in the history of the competition, and this will now be highlighted by his fourth overall series victory.
South Africans have won seven series titles between them, with the sport's legend Ryk Neethling boasting two behind his name.
Le Clos had to work hard for his 200m butterfly victory on Saturday with Daiya Seto of Japan proving a worthy competitor.
Seto held a healthy lead for the majority of the race before Le Clos clawed his way back over the final lap. The South African out-touched Seto with a time of 1:49.25 with the Japanese swimmer claiming a close second place in 1:50.19. Seto’s compatriot Masaki Kaneko was third in 1:52.23.