2021 Estoril Open

{{TennisEventInfo|2021|Estoril Open|

| date = 26 April – 2 May

| edition = 6th

| logo = Estoril_Open_2021.png

| category = ATP Tour 250

| prize_money = €481,270

| draw = 28S / 16D

| surface = Clay / outdoor

| location=Cascais, Portugal

| venue=Clube de Ténis do Estoril

| champs={{flagicon|ESP}} Albert Ramos Viñolas

| champd={{flagicon|MON}} Hugo Nys / {{flagicon|GER}} Tim Pütz

| before_year = 2019

}}

The 2021 Estoril Open is a men's tennis tournament played on outdoor clay courts. It is the 6th edition of the tournament and part of the ATP Tour 250 series of the 2021 ATP Tour. It tames place at the Clube de Ténis do Estoril in Cascais, Portugal, from 26 April through 2 May 2021. Seventh-seeded Albert Ramos Viñolas won the singles title.{{cite web|title=Millennium Estoril Open Overview|url=https://www.atptour.com/en/tournaments/estoril/7290/overview|website=atptour.com}}

Champions

=Singles=

{{flagicon|ESP}} Albert Ramos Viñolas def. {{flagicon|GBR}} Cameron Norrie, 4–6, 6–3, 7–6^(7–3).

=Doubles=

{{flagicon|MON}} Hugo Nys / {{flagicon|GER}} Tim Pütz def. {{flagicon|GBR}} Luke Bambridge / {{flagicon|GBR}} Dominic Inglot, 7–5, 3–6, [10–3].

Points and prize money

= Point distribution =

class=wikitable style=font-size:90%;text-align:center
style="width:130px; background:#dfe2e9;"\|Event \| style="width:80px; background:lime;"\|W \| style="width:85px; background:thistle;"\|F \| style="width:85px; background:#ff0;"\|SF \| style="width:85px; background:#ffebcd;"\|QF \| style="width:85px; background:#afeeee;"\|Round of 16 \| style="width:85px; background:#afeeee;"\|Round of 32 \|width=85 \|Q \|width=85 \|Q2 \|width=85 \|Q1
style="background:#ededed;"\| Singles \|rowspan=2\|250 \|rowspan=2\|150 \|rowspan=2\|90 \|rowspan=2\|45 \|20 \|0 \|12 \|6 \|0
style="background:#ededed;"\| Doubles \| 0 \| {{n/a}} \| {{n/a}} \| {{n/a}} \| {{n/a}}

class=wikitable style=font-size:90%;text-align:center

style="width:130px; background:#dfe2e9;"|Event

| style="width:80px; background:lime;"|W

| style="width:85px; background:thistle;"|F

| style="width:85px; background:#ff0;"|SF

| style="width:85px; background:#ffebcd;"|QF

| style="width:85px; background:#afeeee;"|Round of 16

| style="width:85px; background:#afeeee;"|Round of 32

|width=85 |Q

|width=85 |Q2

|width=85 |Q1

style="background:#ededed;"| Singles

|rowspan=2|250

|rowspan=2|150

|rowspan=2|90

|rowspan=2|45

|20

|12

style="background:#ededed;"| Doubles

| 0

| {{n/a}}

= Prize money =

class=wikitable style=font-size:90%;text-align:center

style="width:130px; background:#dfe2e9;"|Event

| style="width:80px; background:lime;"|W

| style="width:85px; background:thistle;"|F

| style="width:85px; background:#ff0;"|SF

| style="width:85px; background:#ffebcd;"|QF

| style="width:85px; background:#afeeee;"|Round of 16

| style="width:85px; background:#afeeee;"|Round of 32

|width=85 |Q2

|width=85 |Q1

style="background:#ededed;"|Singles

|€41,145

|€29,500

|€21,000

|€14,000

|€9,000

|€5,415

|€2,645

|€1,375

style="background:#ededed;"|Doubles*

|€15,360

|€11,000

|€7,250

|€4,710

|€2,760

| {{n/a}}

_{*per team}

Singles main-draw entrants

=Seeds=

class=wikitable
width="75"\| Country ! width="180"\| Player ! Rank¹ ! Seed
{{flag\|CAN}} \|Denis Shapovalov \|14 \|1
{{flag\|CHI}} \|Cristian Garín \|22 \|2
{{flag\|FRA}} \|Ugo Humbert \|31 \|3
~~{{flag\|JPN}}~~ \|~~Kei Nishikori~~ \|39 \|4
{{flag\|KAZ}} \|Alexander Bublik \|42 \|5
{{flag\|CRO}} \|Marin Čilić \|44 \|6
style="background-color:#cfc;" \|{{flag\|ESP}} \|Albert Ramos Viñolas \|46 \|7
{{flag\|ESP}} \|Alejandro Davidovich Fokina \|48 \|8

class=wikitable

width="75"| Country

! width="180"| Player

! Rank¹

! Seed

|Denis Shapovalov

|14

|Cristian Garín

|22

|Ugo Humbert

|31

~~{{flag|JPN}}~~

|~~Kei Nishikori~~

|39

|Alexander Bublik

|42

|Marin Čilić

|44

style="background-color:#cfc;"

|{{flag|ESP}}

|Albert Ramos Viñolas

|46

|Alejandro Davidovich Fokina

|48

¹ Rankings are as of 19 April 2021{{Cite web|url=https://desporto.sapo.pt/modalidades/tenis/artigos/cinco-tenistas-do-top-20-no-estoril-open-2021|title=Cinco tenistas do 'Top 20' no Estoril Open 2021|website=Desporto Sapo|date=2 April 2021}}

=Other entrants=

The following players received wildcards into the main draw:

~~{{flagicon|JPN}} Kei Nishikori~~
{{flagicon|CAN}} Denis Shapovalov
{{flagicon|POR}} João Sousa{{Cite web|url=https://observador.pt/2021/03/30/joao-sousa-recebe-wild-card-para-o-estoril-open/|title=João Sousa recebe wild card para o Estoril Open|website=Observador|date=2 April 2021}}

The following players received entry from the qualifying draw:

{{flagicon|ESP}} Carlos Alcaraz
{{flagicon|POR}} Nuno Borges
{{flagicon|ESP}} Pedro Martínez
{{flagicon|ESP}} Jaume Munar

The following player received entry as a lucky loser:

{{flagicon|ESP}} Roberto Carballés Baena

= Withdrawals =

;Before the tournament

{{flagicon|ESP}} Pablo Carreño Busta → replaced by {{flagicon|RSA}} Kevin Anderson
{{flagicon|ITA}} Fabio Fognini → replaced by {{flagicon|FRA}} Pierre-Hugues Herbert
{{flagicon|FRA}} Gaël Monfils → replaced by {{flagicon|ITA}} Marco Cecchinato
{{flagicon|JPN}} Kei Nishikori → replaced by {{flagicon|ESP}} Roberto Carballés Baena
{{flagicon|FRA}} Benoît Paire → replaced by {{flagicon|ESP}} Fernando Verdasco
{{flagicon|ARG}} Diego Schwartzman → replaced by {{flagicon|ARG}} Juan Ignacio Londero

;During the tournament

{{flagicon|FRA}} Richard Gasquet

= Retirements =

{{flagicon|RSA}} Kevin Anderson

Doubles main-draw entrants

=Seeds=

class="wikitable"
width="70"\| Country ! width="160" \| Player ! width="70"\| Country ! width="175"\| Player ! Rank¹ ! Seed
{{flag\|FRA}} \|Fabrice Martin \|{{flag\|FRA}} \|Édouard Roger-Vasselin \|40 \|1
{{flag\|RSA}} \|Raven Klaasen \|{{flag\|JPN}} \|Ben McLachlan \|67 \|2
{{flagu\|USA}} \|Austin Krajicek \|{{flag\|AUT}} \|Oliver Marach \|70 \|3
{{flag\|ESA}} \|Marcelo Arévalo \|{{flag\|NED}} \|Matwé Middelkoop \|93 \|4

class="wikitable"

width="70"| Country

! width="160" | Player

! width="70"| Country

! width="175"| Player

! Rank¹

! Seed

|Fabrice Martin

|{{flag|FRA}}

|Édouard Roger-Vasselin

|40

|Raven Klaasen