Top-ranked Novak Djokovic and US Open champion Daniil Medvedev headline the rosters announced for the Davis Cup Finals that begin next month. (More Tennis News)

Djokovic, a 20-time major champion who fell one win short of a calendar-year Grand Slam in 2021, is joined on Serbia’s squad by Filip Krajinovic, Dusan Lajovic, Laslo Djere and Miomir Kekmanovic.

Medvedev, who is ranked No. 2 and claimed his first Grand Slam title by beating Djokovic in the final at Flushing Meadows in September, leads a Russian team that includes No. 6 Andrey Rublev, No. 19 Aslan Karatsev, No. 30 Karen Khachanov and Evgeny Donskoy.

Eighteen countries will participate in group-stage matches starting November 25 on indoor hard courts in Madrid; Innsbruck, Austria; and Turin, Italy. After the quarterfinals in those cities, the semifinals and final will be held in Madrid.

Spain is the reigning champion thanks to its 2019 title; the Davis Cup was called off last year because of the coronavirus pandemic.

Here are the full rosters, listed by groups for the opening stage:

Group A (Madrid)

Russia: Daniil Medvedev, Andrey Rublev, Aslan Karatsev, Karen Khachanov, Evgeny Donskoy.

Spain: Pablo Carre?o Busta, Roberto Bautista Agut, Carlos Alcaraz, Feliciano Lopez, Marcel Granollers

Ecuador: Emilio Gomez, Roberto Quiroz, Diego Hidalgo, Gonzalo Escobar, Cayetano March

Group B (Madrid)

Canada: Felix Auger-Aliassime, Denis Shapovalov, Vasek Pospisil, Brayden Schnur, Peter Polansky

Kazakhstan: Alexander Bublik, Mikhail Kukushkin, Dmitry Popko, Aleksandr Nedovyesov, Andrey Golubev

Sweden: Elias Ymer, Mikael Ymer, Jonathan Mridha, Andre Goransson

Group C (Innsbruck)

France: Ugo Humbert, Arthur Rinderknech, Richard Gasquet, Pierre-Hugues Herbert, Nicolas Mahut

Britain: Cameron Norrie, Daniel Evans, Joe Salisbury, Neal Skupski

Czech Republic: Jiri Vesely, Tomas Machac, Zdenek Kolar, Jiri Lehecka, Lukas Rosol

Group D (Turin)

Croatia: Marin Cilic, Borna Coric, Borna Gojo, Nikola Mektic, Mate Pavic

Australia: Alex de Minaur, John Millman, Jordan Thompson, Alexei Popyrin, John Peers

Hungary: Marton Fucsovics, Attila Balazs, Zsombor Marozsan, Mate Valkusz

Group E (Turin)

United States: John Isner, Reilly Opelka, Taylor Fritz, Jack Sock, Rajeev Ram

Italy: Matteo Berrettini, Jannik Sinner, Lorenzo Sonego, Fabio Fognini, Lorenzo Musetti

Colombia: Daniel Galan, Nicolas Mejia, Juan Sebastian Cabal, Robert Farah

Group F (Innsbruck)

Serbia: Novak Djokovic, Filip Krajinovic, Dusan Lajovic, Laslo Djere, Miomir Kecmanovic

Germany: Jan Lennard Struff, Dominik Koepfer, Peter Gojowczyk, Kevin Krawietz, Tim Puetz

Austria: Dennis Novak, Jurij Rodionov, Gerald Melzer, Oliver Marach, Philipp Oswald.