BBC Sport tennis correspondent Russell Fuller looks at the key questions after a players' union co-founded by Novak Djokovic began legal action against tennis' governing bodies.
Original Source:
https://www.bbc.com/sport/tennis/articles/c78ey959q64o?xtor=AL-72-%5Bpartner%5D-%5Byahoo.north.america%5D-%5Bheadline%5D-%5Bsport%5D-%5Bbizdev%5D-%5Bisapi%5D
