The American and Italian disagree on where the line is in terms of on-court theatrics and fan interaction.
The Frenchman wants to rest and recuperate ahead of 2022.
In what could be a Davis Cup finals prelude, Novak Djokovic will play singles and doubles at the Paris Masters.
One for the ages: King of clay vs. Titan of timelessness.
The former champion is hoping to grow his confidence as the season winds down.
The final three teams were added to the field on Thursday.
The Romanian hopes to pick up confidence to take into the 2022 season.