The 2021 Erste Bank Open was a men's tennis tournament played on indoor hard courts. It was the 47th edition of the event, and part of the ATP Tour 500 Series of the 2021 ATP Tour. It was held at the Wiener Stadthalle in Vienna, Austria, from 25 until 31 October 2021. Second-seeded Alexander Zverev won the singles title.

Finals

Singles

Doubles

Singles main-draw entrants

Seeds

CountryPlayerRank1Seed
GREStefanos Tsitsipas31
GERAlexander Zverev42
ITAMatteo Berrettini73
NORCasper Ruud94
POLHubert Hurkacz105
CANFélix Auger-Aliassime126
ITAJannik Sinner137
ARGDiego Schwartzman148
  • Rankings are as of October 18, 2021

Other entrants

The following players received wildcards into the singles main draw:

The following player received entry using a special exempt:

The following players received entry from the qualifying draw:

The following player received entry as a lucky loser:

Withdrawals

Before the tournament

Doubles main-draw entrants

Seeds

CountryPlayerCountryPlayerRank1Seed
CRONikola MektićCROMate Pavić31
USARajeev RamGBRJoe Salisbury72
AUSJohn PeersSVKFilip Polášek223
COLJuan Sebastián CabalCOLRobert Farah274
  • Rankings are as of 18 October 2021

Other entrants

The following pairs received wildcards into the doubles main draw:

The following pair received entry from the qualifying draw:

The following pair received entry as lucky losers:

Withdrawals

Before the tournament

External links