Daniil Medvedev begins his ATP Finals title defence on Sunday when he opens up the end of season singles event in Turin.
The US Open champion takes on Hubert Hurkacz in the opening Red Group session, before Olympic gold medallist Alexander Zverev takes on Wimbledon runner-up Matteo Berrettini.
World number one Novak Djokovic does not begin his campaign until Monday, when he faces Casper Ruud in the Green Group, while Stefanos Tsitsipas plays Andrey Rublev in his opener.
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Turin is hosting the ATP Finals for the first time, beginning a cycle which lasts until 2025, after 12 years of London taking on the end of season event.
Medvedev is the defending champion, having won all five of his events last year. The event takes place between November 14-21.
A maximum prize pot of £1.7m is on offer if a player can do the same as Medvedev and go unbeaten over all five matches, while a final win is worth around £817,000.
An undefeated champion also earns 1500 ATP ranking points.
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Match of the Day
Hubert Hurkacz has had a breakthrough season and he pulled off a big shock when he knocked Daniil Medvedev out of Wimbledon in the quarter-finals.
The Pole will be hoping to pull off a similar result on day one.
Matteo Berrettini has not had the best few months since his spell on grass, but he has home advantage - and that will put pressure on Alexander Zverev.
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Order of Play - November 14
Pala Alpitour, Turin - Afternoon session (play starts 1030 UK time, singles not before 1300 UK time)
Nikola Mektic/Mate Pavic v Kevin Krawietz/Horia Tecau
Daniil Medvedev v Hubert Hurkacz
Evening session (play starts 1730 UK time, singles not before 2000 UK time)
Marcel Gronollers/Horacio Zeballos v Ivan Dodig/Filip Polasek
Alexander Zverev v Matteo Berrettini
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