The top seeds come into the tournament with question marks. Can they fight through a field with plenty of major champions in the mix?

Will Nikola Mektic and Mate Pavic add to their banner year, or will another duo walk away from the men's season finale as a champion?

Meanwhile, Novak Djokovic is joining the doubles action this week and is off to a winning start with Filip Krajinovic in Paris.

The Croatians will vie for their 10th title of the season, but will have to overcome an exceptionally deep field to do so.