The 2021 Bucharest Challenger was a professional tennis tournament played on clay courts. It was the 1st edition of the tournament which was part of the 2021 ATP Challenger Tour. It took place in Bucharest, Romania between 20 and 26 September 2021.

Singles main-draw entrants Seeds Country Player Rank1 SeedStefano Travaglia991Radu Albot1052Thanasi Kokkinakis1803Zdeněk Kolář1854Sumit Nagal1865Maximilian Marterer1976Vít Kopřiva1987Jiří Lehečka2018 1 Rankings are as of 13 September 2021.

Other entrants The following players received wildcards into the singles main draw: Nicolae Frunză David Ionel Ștefan Paloși

The following players received entry into the singles main draw as alternates: Filip Jianu Alexey Vatutin

The following players received entry from the qualifying draw: Matteo Arnaldi Ivan Gakhov Calvin Hemery Dragoș Nicolae Mădăraș

Champions Singles

Jiří Lehečka def. Filip Horanský 6–3, 6–2.

Doubles

Ruben Gonzales / Hunter Johnson def. Maximilian Marterer / Lukáš Rosol 1–6, 6–2, [10–3].

References