Carlos Alcaraz and Jannik Sinner headline ATP Finals groups, but doubt remains over Novak Djokovic

This year's lucrative season-ending event will be staged from November 9 to 16 at the Inalpi Arena in Turin and Alcaraz is the top seed and sits at No. 1 in Group Jimmy Connors, while second seed Sinner takes top spot in Group Bjorn Borg, with the seedings based on the November 10 ATP Rankings.

Six-time Grand Slam winner Alcaraz has been handed a tough task as he has been paired with seven-time ATP Finals champion Novak Djokovic, with American No. 1 Taylor Fritz and Alex de Minaur also in the group.

Defending champion Sinner will face third seed Alexander Zverev and they will be joined by Ben Shelton, and - as things stand - Felix Auger-Aliassime.

The full schedule and order of play are yet to be confirmed, but the first singles match is set to start at 14:00 local time on Sunday with the second match scheduled to get underway at 20:30.

24-time Grand Slam winner Djokovic went into Thursday's draw as the fourth seed, but he is yet to confirm if he will actually play as he told the media earlier this week that "I will decide at the end of this tournament".

But here is the tricky part, if Djokovic reaches the final at the ongoing Hellenic Championship, then he will play on Saturday November 8 before dashing off to Turin for the ATP Finals.

Of course, that is not such a big deal in modern tennis as the players use private jets and both tournaments are in Europe.

There is also the small matter of Lorenzo Musetti still being in with a chance of qualifying for the season-ending tournament, which could add another twist.

The Italian is currently ninth in the Race To Turin with Auger-Aliassime occupying the eighth and final spot, but if Musetti wins the Hellenic Championship then he will replace the Canadian in the draw and will go into Group Bjorn Borg.

Now, to add further confusion, should Djokovic decide not to play in Turin, both Auger-Aliassime and Musetti will then play at the year-end tournament.

If Musetti wins the Hellenic Championship title, he will get an automatic entry and will thus go into Group Bjorn Borg while Auger-Aliassime will be the alternate for Djokovic and take the Serb's place in Group Jimmy Connors.

If, however, Musetti fails to overtake Auger-Aliassime in the rankings, then he will be the alternate to replace Djokovic with the Canadian remaining in Sinner's group.

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