The 2021 ATP Lyon Open (also known as the Open Parc Auvergne-Rhône-Alpes Lyon) was a men's tennis tournament played on outdoor clay courts. It was the fourth edition of the Lyon Open and part of the ATP Tour 250 series of the 2021 ATP Tour. It took place in the city of Lyon, France, from 15 May through 22 May 2021. Second-seeded Stefanos Tsitsipas won the singles title.[1]
See main article: 2021 ATP Lyon Open – Singles.
Cameron Norrie, 6–3, 6–3See main article: 2021 ATP Lyon Open – Doubles.
Pierre-Hugues Herbert / Nicolas Mahut, 6–4, 5–7, [10–8]| Event | W | F | SF | QF | Round of 16 | Round of 32 | width=85 | Q | width=85 | Q2 | width=85 | Q1 |
| Singles | 250 | 150 | 90 | 45 | 20 | 0 | 12 | 6 | 0 | |||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubles | 0 |
| Event | W | F | SF | QF | Round of 16 | Round of 32 | width=85 | Q2 | width=85 | Q1 |
| Singles | €41,145 | €29,500 | €21,000 | €14,000 | €9,000 | €5,415 | €2,645 | €1,375 | ||
| Doubles* | €15,360 | €11,000 | €7,250 | €4,710 | €2,760 |
| Country | Player | Rank1 | Seed | |
|---|---|---|---|---|
 Austria | Dominic Thiem | 4 | 1 | |
| Stefanos Tsitsipas | 5 | 2 | ||
 Argentina | Diego Schwartzman[2] | 10 | 3 | |
 Belgium | David Goffin | 13 | 4 | |
| France | Gaël Monfils | 15 | 5 | |
 Italy | Jannik Sinner | 18 | 6 | |
 Canada | Félix Auger-Aliassime | 21 | 7 | |
 Russian Federation | Karen Khachanov | 24 | 8 |
The following players received wildcards into the singles main draw:
The following player received entry as an alternate:
The following players received entry from the qualifying draw:
The following players received entry as lucky losers:
Matteo Berrettini → replaced by Corentin Moutet Jérémy Chardy → replaced by 
Yoshihito Nishioka Dan Evans → replaced by Pierre-Hugues Herbert
Taylor Fritz → replaced by Cameron Norrie
Thiago Seyboth Wild
John Millman → replaced by Gilles Simon
Albert Ramos Viñolas → replaced by Arthur Rinderknech Lorenzo Sonego → replaced by Lorenzo Musetti| Country | Player | Country | Player | Rank1 | Seed | |
|---|---|---|---|---|---|---|
| France | Pierre-Hugues Herbert | France | Nicolas Mahut | 27 | 1 | |
 Finland | Henri Kontinen | France | Édouard Roger-Vasselin | 46 | 2 | |
| United Kingdom | Ken Skupski | United Kingdom | Neal Skupski | 77 | 3 | |
| Hugo Nys | Tim Pütz | 106 | 4 |
The following pairs received wildcards into the doubles main draw:
The following pair enters with a protected ranking into the doubles main draw:
Jérémy Chardy / Fabrice Martin → replaced by Marc López / Fabrice Martin
Marcus Daniell / Philipp Oswald → replaced by 
André Göransson / 
Andrei Vasilevski
Jonathan Erlich / Lloyd Harris → replaced by Artem Sitak / João Sousa John Millman / 
Divij Sharan → replaced by Sander Arends / Divij Sharan
Aisam-ul-Haq Qureshi / Andrea Vavassori → replaced by 
Aleksandr Nedovyesov / Andrea Vavassori