Here is our preview of this week's action on the ATP and WTA Tours.
Swiss Indoors Basel
The race to qualify for the season-ending Finals in Turin takes centre stage this week, with 39-year-old Novak Djokovic opting to play the Swiss ATP 500 event for the first time since 2011.
The Serb, currently 11th in the Live Race, takes on France's Ugo Humbert in the opening round, as he looks to strengthen his bid for a record 19th appearance at the ATP Finals.
Djokovic has been placed in the same half of the draw as top seed Ben Shelton, with the US Open runner-up searching for form after a disappointing third-round exit at the Shanghai Masters.
The Basel draw contains three other players in the hunt for a place at the ATP Finals: Arthur Fils, Rafael Jodar and Taylor Fritz.
Second-seeded Fils faces either a qualifier or lucky loser, Jodar takes on Alejandro Tabilo, while Fritz opens his tournament against Stefanos Tsitsipas.
Meanwhile, it promises to be an emotional week for three-time major champion Stan Wawrinka, who will officially retire from tennis after his Basel campaign. The 41-year-old faces eighth seed Jiri Lehecka in the first round.
Check out the full draw in Basel here!
Vienna Open
Carlos Alcaraz is the star name in a stacked draw in Vienna, as the Spaniard looks to bounce back from a surprise early exit in Shanghai with a fast start to his European indoor hard-court swing.
The world number three will need to hit the ground running at the ATP 500 event, with former top-10 star Karen Khachanov lying in wait in the first round.
Daniil Medvedev, champion in Almaty last week, can bolster his chances of making the ATP Finals with another deep run in Vienna. Currently fifth in the Live Race, the Russian faces Daniel Merida Aguilar in his tournament opener.
It's also a crucial week for Flavio Cobolli, Alex De Minaur and Frances Tiafoe, with all three men looking to claim valuable points in their pursuit of a place in Turin next month.
Elsewhere, top seed Alexander Zverev will officially become world number one for the first time with a run to the quarter-finals in Austria. The German takes on wildcard Martin Landaluce in his opening match.
View the full Vienna draw right here!
Pan Pacific Open
Iga Swiatek and Marta Kostyuk are among the notable names to pull out of the Pan Pacific Open with injury, as both players miss out on qualification for the year-end Finals, with the lineup in Indian Wells now complete.
Nevertheless, it remains an intriguing draw at the WTA 500 event in Tokyo, with world number one Elena Rybakina and Wuhan champion Maja Chwalinska the top two seeds.
Both Rybakina and Chwalinska receive first-round byes, along with third seed Diana Shnaider and fourth seed Belinda Bencic.
Home favourite Naomi Osaka takes on former world number four Jasmine Paolini in a blockbuster first-round match, while Elise Mertens, Alexandra Eala and Leylah Fernandez will all fancy their chances of a productive week to round off the Asian swing.
Take a look at the full draw here!
Guangzhou Open
Staying in Asia, the WTA 250 event in Guangzhou looks to be a great opportunity for those positioned lower in the rankings, as Ukraine's Daria Snigur competes as the top seed.
Wildcard Venus Williams takes on Austrian teenager Lilli Tagger in a standout first-round clash, while Janice Tjen, Paula Badosa and Sofia Kenin are among the other notable names in the draw.
