The 2021 ATP Finals was a men's tennis tournament played on indoor hard courts at the Pala Alpitour in Turin, Italy, from 14 to 21 November 2021. It was the season-ending event for the highest-ranked singles players and doubles teams on the 2021 ATP Tour.

Alexander Zverev is a German professional tennis player. He has been ranked by the ATP as high as world No. 2. Zverev's singles career highlights include a gold medal at the 2020 Tokyo Olympics, and titles at the 2018 and the 2021 ATP Finals. He has won 21 ATP Tour titles in singles and two in doubles, and contested a major final at the 2020 US Open.