| 2021 Bratislava Open | |
|---|---|
| Date | 7–13 June |
| Edition | 2nd |
| Category | ATP Challenger Tour |
| Surface | Clay |
| Location | Bratislava, Slovakia |
| Champions | |
| Singles | |
 Tallon Griekspoor | |
| Doubles | |
 Denys Molchanov /  Aleksandr Nedovyesov | |
The 2021 Bratislava Open was a professional tennis tournament played on clay courts. It was the 2nd edition of the tournament which was part of the 2021 ATP Challenger Tour. It took place in Bratislava, Slovakia between 7 and 13 June 2021.
| Country | Player | Rank1 | Seed |
|---|---|---|---|
 SVK | Norbert Gombos | 81 | 1 |
 ARG | Federico Coria | 94 | 2 |
 BOL | Hugo Dellien | 124 | 3 |
| SVK | Jozef Kovalík | 127 | 4 |
| NED | Tallon Griekspoor | 131 | 5 |
| ARG | Juan Manuel Cerúndolo | 147 | 6 |
 SLO | Blaž Rola | 155 | 7 |
 POR | Frederico Ferreira Silva | 168 | 8 |
The following players received wildcards into the singles main draw:
The following player received entry into the singles main draw using a protected ranking:
The following players received entry from the qualifying draw:
The following player received entry as a lucky loser:
Tallon Griekspoor def. Sebastián Báez 7–6(8–6), 6–3. Denys Molchanov / Aleksandr Nedovyesov def. Sander Arends / 
Luis David Martínez 7–6(7–5), 6–1.The 2016 Slovak Open was a professional tennis tournament played on indoor hard courts. It was the 17th edition of the tournament which was part of the 2016 ATP Challenger Tour. It was also the 8th edition of the tournament which was part of the ITF Women's Circuit. It took place in Bratislava, Slovakia between 7 and 13 November 2016.
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