- Source: 2021 Antalya Challenger III
The 2021 Antalya Challenger III was a professional tennis tournament played on clay courts. It was the third edition of the tournament which was part of the 2021 ATP Challenger Tour. It took place in Antalya, Turkey between 29 November and 5 December 2021.
Singles main-draw entrants
= Seeds
=1 Rankings as of 22 November 2021.
= Other entrants
=The following players received wildcards into the singles main draw:
Yankı Erel
Cem İlkel
Aleksandre Metreveli
The following players received entry into the singles main draw as alternates:
Hsu Yu-hsiou
Lee Duck-hee
The following players received entry from the qualifying draw:
Tiago Cação
Oliver Crawford
Mick Veldheer
Louis Wessels
Champions
= Singles
=Nuno Borges def. Ryan Peniston 6–4, 6–3.
= Doubles
=Riccardo Bonadio / Giovanni Fonio def. Hsu Yu-hsiou / Tseng Chun-hsin 3–6, 6–2, [12–10].