India, March 20 -- The tennis world has been hit with fresh controversy after Novak Djokovic's Professional Tennis Players Association (PTPA) filed a lawsuit against the world's major tennis bodies; the ATP, WTA, ITF and ITIA.

The PTPA labelled the world bodies as a 'cartel' and accused the organisations of mismanagement and inequality in tennis.

The PTPA is backed by American billionaire Bill Ackman, who has publicly endorsed Donald Trump in the US presidential race. He is a tennis fan and is reported to have financially supported the PTPA in its early days, after it was founded by Djokovic and Vasek Pospisil. Trump has intervened in the ongoing tussle between PGA Tour and LIV Golf, and has tried helping him find a resolution.

After t...